Glossary of Terms

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The abdomen is that part of the body, lying between the chest and pelvis, containing the digestive organs (i.e. the belly).
Localised accumulation of pus in a cavity; usually associated with infection. A common outcome of cat fights.
A rapid and often severe onset. (e.g. acute infection). 

Ad lib
Short for ad libitum, meaning without restraint or restriction.  Usually used to describe having food or water available at all times.

Addison's Disease
Is a rare disorder in which the adrenal glands produce insufficient steroid hormones (corticosteroids). Lifelong treatment with steroid replacement therapy is required, with regular follow-up treatment and monitoring for other health problems.
Pertaining to food or the digestive tract (e.g. alimentary canal is the entire digestive tract from the mouth through to the large intestines and rectum).
An allergen is a substance that can cause an allergic reaction. In allergic animals, the immune system recognises allergens as "foreign" or "dangerous" and responds accordingly. In non-allergic animals these substances cause no immune response.
Loss of hair from the head or body. Hair loss, or alopecia, can have a variety of causes, including parasites, hormone imbalance, food allergies and infection. In order to treat your pet’s skin problem, it is important to identify the cause.
The relief of pain. An analgesic is something designed to relieve pain.
Anaphylaxis refers to a rapidly developing and serious allergic reaction that affects a number of different areas of the body at one time. Severe anaphylactic reactions can be fatal.
A lower than normal level of red blood cells (also referred to as erythrocytes) carrying oxygen to the body.
Anaesthesia is the total loss of feeling or sensation. It is induced with drugs to allow surgery or procedures to be performed without causing pain. Anaesthesia may be applied to the whole body, when it is known as general anaesthesia, or to part of the body, when it is known as local anaesthesia.
Loss of appetite, whatever the cause.
A compound or substance that kills or slows down the growth of bacteria. Antibiotics are not effective against viral infections.


A medication or product that counteracts a poison.  Not all poisons have an antidote, but when one is available it greatly helps in the treatment of the toxicity.

Also known as an immunoglobulin is a large Y-shaped protein to identify and neutralise foreign antigens like bacteria and viruses. The body can create a short-term library of antibodies, and this is what we contribute to with vaccination.
A medication used to treat vomiting and nausea.
A medication used to treat fungal infections such as ringworm.
A substance that triggers the production of an antibody. The immune system recognises an antigen as a foreign and potentially harmful invader (e.g. bacteria and viruses).
A medication to relieve itching.
A medication to reduce a fever or high temperature. 

An antibody made by the body against a particular toxin.  These can be isolated to produce an antitoxin injection for cases of toxicity.  For example, a tetanus antitoxin is available, and is used to neutralise any toxin currently in the blood stream.  Antitoxin injections are very useful for acute toxicities, but have no lasting effect, so vaccination is still recommended to then produce the longer-lasting protection.

A medication to relieve coughing. Veterinarians often prescribe antitussive medications to pets that suffer from conditions that cause severe or intense coughing, such as canine cough.
Opening at the end of an animal’s digestive tract where faeces are expelled.
Disruption in the regularity of the heartbeat. They occur when the electrical impulses to the heart that co-ordinate heartbeats are not working properly, making the heart beat too fast, too slow or inconsistently. 

Temporarily not breathing.

Pertaining to a joint.
The build-up of additional fluid in the abdomen, otherwise called the peritoneal cavity.
To draw in or out using a sucking motion. We may take an aspirate from a lump by drawing out a sample of cells for examination. Aspiration can also mean breathing in a foreign object (such as inhaling food into the airway).
If a patient is a carrier for a disease or infection but is not experiencing clinical signs. These animals may still be able to pass the disease on to other animals.
A neurological sign that consists of a lack of motor coordination of muscle movements. It often manifests as wobbliness or unsteadiness in animals, especially when walking.
Is a predisposition toward developing certain allergic reactions to environmental allergens. Commonly used to describe atopic dermatitis, which results in skin irritation and inflammation.

Atrial Fibrillation
An irregular heart rhythm associated with disorganised electrical activity in the upper two chambers of the heart (atria). Its name comes from the fibrillating (i.e. quivering) of the heart muscles of the atria, instead of a coordinated contraction. The result of the rapid, irregular beats is ineffective filling of the ventricles, the bottom two chambers of the heart that pump blood out to the body.
Most commonly refers to the small upper chambers of the heart through which blood enters the heart, as opposed to the larger ventricles, which pump the blood out.  The atria are responsible for helping fill the ventricles and for control of the heart rate.
Atrophy is the progressive decrease in the size of an organ or tissue.  This is usually a result of disuse, especially disuse of muscles.
Weakened. Normally refers to an attenuated vaccine whereby the disease-causing abilities of the vaccine components are weakened or attenuated during the manufacturing process to make them safe upon administration.
Auscultation is a method used to listen to the sounds of the body during a physical examination, usually with a stethoscope.
A medical condition characterised by an overactive immune system which attacks the body, mistaking normal tissues in the body for harmful substances. 

Tearing away of a structure, such as the avulsion of nerves to the front legs as part of a traffic accident or other trauma, or the avulsion of a tendon off of a bone.

A medical condition characterised by abnormally high levels of nitrogen-containing compounds, such as urea and creatinine, commonly as a result of kidney malfunction or dehydration.


A bacterium is a unicellular microorganism which represents one of the most basic and primitive forms of life. Bacteria are everywhere.  Some bacteria are capable of causing disease in animals. 

A chemical element that blocks X-rays, so appears white on radiographs.  This can be swallowed for a 'barium study' in which a series of radiographs allows us to track the progress of the barium through the intestines.  Barium studies are especially useful if an obstruction of the intestines is suspected.
Meaning two sides.
A green/yellow liquid formed in the liver. Bile plays a vital role in the digestion of fats.
The removal of a sample of tissue or cells from a living subject to determine the presence or extent of a disease.
A female dog.
A sac that receives and holds a liquid until it is excreted.  Often refers to the urinary bladder. 

Swelling of the eyelids, usually with conjunctival swelling also.

A medical condition in which the stomach becomes overstretched by excessive gas. Bloat is a very serious health risk for many deep-chested dogs.  In some cases the stomach can also twist, which is an emergency.
Blood Glucose
The amount of glucose (sugar) present in the blood.
Bone Marrow

Bone marrow is a spongy, fatty tissue that houses stem cells, located inside a few large bones. These stem cells transform themselves into white and red blood cells and platelets.
The rumbling noise caused by the movement of gas through the stomach and/or intestines.


Having a short, wide face.  Brachycephalic breeds include Pugs, Boxers, Pekingese, Persians.  These breeds are more likely to have difficulty breathing due to their conformation.

An abnormally slow heart rate.

The large airways within the lungs.
A substance that dilates the airways in the lungs.
Blood urea nitrogen (BUN) measures the amount of urea nitrogen, a waste product of protein metabolism, in the blood.  It can be used as an aid to measure kidney function.


Part of the gastrointestinal tract between the small and large intestines. It is a small, coiled organ in dogs. 

Severe weight loss, especially with loss of muscle mass.  Also may be called emaciation.  Is a sign of severe disease, such cancer, renal failure or heart failure.


The build-up of calcium salts in soft tissue, causing it to harden.
A concretion of material, usually mineral salts, that forms in an organ of the body. Bladder or kidney stones are an example of calculus.


Small patch of thickened skin, generally unhaired, that forms on pressure points such as the elbows and hocks.  Also the term used for the bone growth during the repair of a bone fracture.

A class of disease in which a group of cells display uncontrolled growth and invasion that intrudes upon and destroys adjacent tissues. Cancers sometimes spread to other locations in the body. This term is normally used to describe malignant tumours.
This fungus or yeast can normally be found in areas of the body such as the mouth, the genital and intestinal tracts. It can cause disease in animals.
Pertaining to dogs.
A subtype of cancer that arises from epithelial cells. Epithelial cells form the lining of our internal organs, cavities, glands, and skin.
Pertaining to the heart.
Literally means "heart muscle disease".

A term relating to both the heart and lungs.
Refers to the circulatory system comprising the heart and blood vessels which carries nutrients and oxygen to the tissues of the body and removes carbon dioxide and other wastes.
The animal equivalent of our wrist.

The desexing procedure in males that involves the removal of the testicles.
White opacities in the lens of the eye. Cataracts are one of the most common problems affecting the eyes of the dog. There are many different forms and causes of cataract formation. Severe cataracts can cause blindness and may be an indicator of underlying diseases like diabetes.
A term meaning toward the tail or the posterior end of the body. 

Central Nervous System (CNS)
Consists of the brain and spinal cord.  The control centres for the body.

A region of the brain that plays an important role in motor control and co-ordination.
A region of the brain that controls emotional, behavioural and learning functions.
Treatment of cancer with drugs. The drugs used are slightly more toxic to cancer cells than healthy cells, so the cancer is treated without causing permanent damage. 

Cherry Eye
A condition in which the tear-producing gland of the third eyelid everts, producing a small 'cherry' of tissue in the inner corner of the eye. 

Inflammation of the bile duct. 
Inflammation of the gall bladder. 
A disease of slow onset and of long duration. (e.g. chronic osteoarthritis)


A condition seen in cats in which the chest fills with a substance called chyle, a milky material that flows through the lymphatic system.

A chronic disease of the liver whereby healthy tissue is replaced by scar tissue.
The process by which the body forms a blood clot (thrombus) that prevents further blood loss from damaged tissues, blood vessels or organs.
A defect in the body's mechanism for making blood clots.
Coccidia are microscopic, single celled organisms that infect animal cells. They can cause watery or bloody diarrhoea in pets.
Inflammation of the large intestine (colon).
The section of the large intestine extending from the caecum to the rectum.
Colostrum is an antibody-rich milk which is secreted by all female animals during the first few days of a newborn’s life.  This is essential for the newborn's immune defences to prevent disease for the first weeks of life until their own immune system can start working fully.  Animals that did not receive colostrum within 24 hours of birth are very prone to severe infections during these first weeks of life.
A state of unconsciousness from which an animal cannot be awakened. 

Also called blackheads.  Small plugs of debris within the hair follicle, often also containing bacteria.  These are seen with certain skin conditions, such as feline acne, demodex mite infection, and hyperadrenocorticism (Cushing's disease).
Complete Blood Count
A complete blood count (CBC), also known as full blood count (FBC) or blood panel, is a test that gives information about the cells in a patient's blood. It is used to evaluate overall health and detect a wide range of disorders, including anaemia and infection.
Computerised Tomography Scan (CT Scan)
Also called computerised axial tomography (CAT) scan, combines a series of X-ray views taken from many different angles to produce cross-sectional images of the bones and soft tissues inside your pet’s body. 

Rounded projection on a bone, usually at joints, for example knuckles.
A condition that is present at birth.
The tissue lining the inner surface of the eyelids and covering the white of the eyes (sclera).
Inflammation of the conjunctiva.  This can have many different causes, including infections, foreign bodies, and trauma.
A condition in which bowel movements occur less often than usual or consist of hard, dry stools that are painful or difficult to pass. 

Contrast agent
Something used to highlight certain areas of interest for radiographs.  There are different substances for use depending on the requirements.  Barium is a common agent that show as white on X-rays that can be swallowed to show the stomach and intestines.  Alternatively, iodine can be injected into the blood stream or into areas, again showing up white on X-rays.  Air is sometimes used to produce black on radiographs when looking at areas such as the bladder. 
A bruise.  Injury to a tissue without breaking the skin allows blood to collect leading to a bruise.  Can also get internal contusions, for example in the lungs following a hit from a car.
The eating of faeces. Is considered normal behaviour in some species, such as rabbits. However, in other species coprophagy can be related to certain diseases or behavioural problems.
Core Vaccine
Vaccines which are strongly recommended, and sometimes even required.  For example, parvovirus vaccine in dogs or panleucopenia in cats.
The clear front part of the eye.
Any of the steroid hormones produced by the adrenal gland or their synthetic equivalents.
Pertaining to the head or in the direction of the head. 

A sac of the oesophagus just before it enters the chest in domestic birds.  Following food, the crop can be felt as a swelling in this area.  When force-feeding or medicating the bird, you may be asked to use a metal tube to reach the crop directly as the most efficient way of giving the medication.  Certain bird diseases will affect the crop and result in problems with digestion.
Cruciate Ligaments
A pair of ligaments within the knee that help to keep the knee stable.  There is a cranial cruciate ligament that stops forward movement and a caudal cruciate ligament that stops backward movement of the knee while walking.  If these are damaged, the knee becomes unstable, and surgery may be required to stabilise the joint again.

The propagation of microorganisms in a growth media. Used to diagnose and guide treatment for infectious diseases.
Cushing’s Syndrome
A condition where abnormalities in either the pituitary gland or adrenal glands cause the release of too much natural cortisone (corticosteroid).

Relating to, or affecting the skin.
A bluish colour of the skin and the mucous membranes due to insufficient oxygen in the blood.
A pathologic space in bone or soft tissue containing fluid or semi-solid material.
Inflammation of the urinary bladder.
Refers to a branch of pathology that deals with making diagnoses of diseases based on the examination of cells.


The excessive loss of body water, without sufficient water intake to replace the deficit. 

Loss of normal intellectual capacity, irrational behaviour, or very vague behaviour.  Similar to Alzheimer's disease in humans.
Pertaining to the skin.
Inflammation of the skin.
Diabetes Mellitus
A disease where the body is unable to absorb sugars (glucose). It is commonly treated with insulin.
Diagnostic Test
A test to determine the presence or cause of disease.
Excessive and frequent evacuation of watery faeces, usually indicating gastrointestinal distress or disorder.
Digestive System
The organs responsible for the transit and metabolism of food in the body. These organs include salivary glands, mouth, oesophagus, stomach, small intestine, liver, gall bladder, pancreas, colon, rectum, and anus.
Dilated Cardiomyopathy
A disorder in which the chambers of the heart are dilated (enlarged). The heart muscle is weakened and cannot pump effectively.
A cleaning process which destroys most microorganisms, but not highly resistant forms.
An infectious viral disease occurring in dogs.  Clinical signs include loss of appetite, a discharge from the eyes and nose, vomiting, fever, lethargy, partial paralysis and sometimes death.
A substance that increases the production of urine.

Domestic Animal
An animal that is not wild and is kept as a pet or to produce food.
Dry Eye
Also known as keratoconjunctivitis sicca (KCS), is a condition that results from the inadequate production of tears.
The first part of the small intestine. The duodenum extends from the stomach to the jejunum (the second part of the small intestine).
Duration of Immunity
Length of time an animal is protected from a disease after vaccination. Vaccines for some diseases provide a long duration of immunity, others only provide immunity for up to a year.

Difficulty in swallowing.
A term used in pathology  meaning abnormal development of tissues.
Difficult or laboured breathing; shortness of breath.
Difficult birth.

Painful or difficult urination.


Ear Canal
The narrow tube, between the ear and ear drum, through which sound enters the ear.
Ear Drum
The thin membrane that separates the middle ear from the external ear. Also called the tympanic membrane.
Ear Mites
Mites that live in the ears of animals. They can just barely be seen as small white dots with the naked eye.
An electrocardiogram (ECG) is a test that records the electrical activity of the heart.
A test that uses sound waves to create a moving picture of the heart (i.e. an ultrasound of the heart). 

A condition seen in early lactation in which the mother has insufficient calcium in their diet, so uses her own supply of calcium to produce milk for her pups or kittens.  This leads to life-threatening
low calcium levels.  Initially seen as panting and restlessness, it can progress to tremors and seizures.  Also called postpartum hypocalcaemia or milk fever.
A parasite, such as a flea, that lives on the exterior of an animal.

Meaning "out of place." (e.g. an ectopic pregnancy is one that has implanted outside the reproductive system)
In medicine, certain mineral elements that are critically important to life, including sodium, potassium, chloride, calcium, and phosphorous.  Even small imbalances in electrolytes can be life-threatening.

Elizabethan Collar
A medical device that is shaped like a cone and is used to prevent the animal from biting, licking, and scratching at wounds and injuries while they heal.
A wasted condition of the body.
Inflammation of the brain.
Disease, damage, or malfunction of the brain.
Pertaining to hormones and the glands that make them. These hormones regulate an animal's growth, physiology and sexual development.
A lighted medical instrument used to get examine hollow organs such as the oesophagus, stomach or airways.
Endotracheal Tube
A breathing tube placed into the trachea. Commonly used during anaesthesia to facilitate delivery of oxygen and anaesthetic to the lungs.

Inflammation of the intestine, especially the small intestine.

The act of injecting a poisonous material (venom) by sting, spine or bite.
Enzymes are proteins that increase the rate of chemical reaction. Almost all processes in a cell need enzymes to occur at significant rates.
The outer layer of the skin.


Excessive tear production.

Technical name for bleeding from the nose.

Redness of the skin resulting from dilation of blood vessels caused by irritation or injury to the tissue.
A red blood cell.


Bodily waste matter derived from ingested food that is discharged through the anus; also called stools.

Of or relating to cats.
Fine Needle Aspirate
A diagnostic procedure sometimes used to investigate superficial (just under the skin) lumps or masses. In this technique, a thin, hollow needle is inserted into the mass to extract cells that, after being stained, will be examined under a microscope.  This is the least invasive way to collect a cell sample.
FIV (Feline Immunodeficiency Virus)
A virus that specifically infects cats (not people).  It is transmitted by cats biting one another, especially during fights.  FIV is the cause of Feline AIDS (Acquired Immune Deficiency Syndrome) – a progressive deficiency of the immune system that can limit the ability of the cat to fight off other infections.
Generating excessive gas in the gastrointestinal tract
FLUTD (Feline Lower Urinary Tract Disease)
Describes a collection of conditions that can affect the urinary tract (bladder and/or urethra) of cats. Common clinical signs include straining to urinate and blood in the urine. 

An unborn animal in the later stages of development showing recognisable features of the mature animal.


A small cavity or deep narrow-mouthed depression (e.g. hair follicle)

Foreign Body
Any abnormal substance within the body.  Commonly used to describe foreign material under the skin (eg splinters, glass) or in the gastrointestinal tract (e.g. toys, balls, bones).
Breaking of hard tissue such as bone. May be caused by trauma or bone disease.


The manner of walking or moving. Assessed to determine the cause of lameness in animals.
Relating to or involving the stomach.
Inflammation of the lining of the stomach.
Relating to the stomach and intestines.
The carrying of an embryo or foetus (i.e. pregnancy).
Pertaining to the gums.
Inflammation of the gums.

A disease of the eye caused by increased pressure within the eyeball.  Glaucoma can lead to damage of the optic disc and loss of vision.
The excretion of glucose in the urine. Normally, urine does not contain glucose as the kidneys are able to reclaim glucose back into the bloodstream.  Glucosuria is usually an indication of diabetes, though it can also be caused by stress and other conditions.

A mass or nodule of chronically inflamed tissue.


A malignant tumour of the blood vessels, usually occurring in the skin, liver or spleen.
The volume of red blood cells in a sample of blood after it has been centrifuged (spun at high speeds). The PCV (Packed Cell Volume), or haematocrit, is expressed as a percentage. For example, normal for dogs is 40-59% and for cats is 29-50%.
The study of blood and diseases of the blood.
A localised swelling filled with blood outside the blood vessels. Usually occurs due to haemorrhage.
The presence of blood in the urine; often a clinical sign of urinary tract disease.


Smelly breath.  Usually an indicator of dental disease.

Also known as Dirofilaria immitis, this is a parasite that is spread from host to host via the bites of mosquitoes. The natural host is the dog but it can also infect cats and ferrets too. The worms mature in the heart and may cause a physical blockage as well as thickening of the heart and associated blood vessels. 
Relating to, affecting, or associated with the liver.
Inflammation of the liver.
Abnormal enlargement of the liver.
Protrusion of an organ through a wall of the cavity in which it is normally enclosed (eg. Umbilical hernia).
A chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the animal.
A living animal on or in which a parasite lives.
The progeny of two animals of different races, breeds, varieties or species.

An abnormal increase in the amount of fluid (CSF) within the skull or brain. This may cause increased pressure inside the skull and progressive enlargement of the head, brain damage and even death.
A prefix meaning more than normal.
High levels of glucose in the blood.
An abnormal increase in the number of cells in a tissue or organ.  This results in an enlargement of the organ.  However, the cells are still the normal (non-cancerous) cells of the organ.
An allergic condition in which the body overreacts to certain substances, such as a bee sting or medication.
High blood pressure.

Elevated body temperature.  If the body overheats, there may be damage to the brain, and it may ultimately be fatal.
Increased production of thyroid hormones caused by an overactive thyroid gland. This condition is more commonly seen in cats, and presents as an increase in appetite, weight loss, and a straggly coat.
An enlargement of an organ or a tissue as a result of an increase in the size of cells (rather than the number as in hyperplasia).
To breathe excessively hard and fast causing blood gas disorders. 

Blood within the front chamber of the eye, in front of the iris.  This is most commonly caused by trauma to the eye.  While the blood itself will be returned to the body, while it is in the eye is may cause further damage, or lead to glaucoma.
A prefix meaning less than normal.
Low levels of glucose in the blood.
Incomplete formation of a structure or organ in the body.
Low blood pressure.
An abnormally low body temperature.
Decreased production of thyroid hormones caused by an underactive thyroid gland. This condition is more commonly seen in dogs, and results in weight gain, reduced appetite, and general lethargy.
Deficiency in the amount of oxygen delivered to the body tissues.


Also known as jaundice.  It is a yellow discolouration of the skin, mucous membranes or whites of the eyes due to excessive levels of bilirubin in the blood.
Disease arising from an unknown cause.


The last part of the small intestine, before the large intestine.

Lack of motility within the gastrointestinal tract.
Immune System
The system that protects the body from foreign substances, cells, and infections.

Describes conditions which result from abnormal activity of the body's immune system, in which the immune system starts targeting and attacking normal body cells. For example, immune mediated haemolytic anaemia (IMHA), is a disease in which the body's immune system destroys the body's own red blood cells.
A condition in which the animal's immune system has been primed and is able to protect the body from a disease-causing agent such as a virus or bacteria.  The aim of vaccination is to induce immunity against common, serious infections.
The creation of immunity usually against a particular disease. Vaccination is a way to produce immunisation. However, a vaccinated animal is not always immune. If the body did not respond appropriately to the vaccine or if the vaccine was not administered correctly, immunity may not be stimulated.  The immunity from a vaccine only lasts a certain time before a booster vaccination is required.

Immunological disorder in which the body's immune system is inadequate and resistance to infectious diseases is reduced.  Can be caused by viral infections such as feline immunodeficiency virus (FIV) in cats.
Pertaining to a substance that suppresses the immune system.  Animals are more prone to infection while on immunosuppressive treatment.
Inactivated Vaccine
Vaccines which are made by taking the real, disease-causing viruses (or bacteria), killing them, and putting them into a liquid base. Also called a killed vaccine.
Loss of control of urination or defecation.
Incubation Period
The period between infection and the appearance of clinical signs of the disease.
Pathological state resulting from the invasion of the body by microorganisms, such as bacteria or viruses.
Refers to the state of being invaded or overrun by parasites.
A local response to injury that is characterised by redness, heat, pain, swelling, and often loss of function.
Tending to occur among members of a family. Genetically transmitted features.
Inborn. A permanent characteristic present since birth.
A hormone secreted by the pancreas to regulate glucose in the body.
Insulin-dependent Diabetes Mellitus (IDDM)

Insulin-dependent diabetes mellitus is a form of diabetes in which patients have little or no ability to produce insulin and are therefore entirely dependent on insulin injections.

Insulin Resistance
A condition where insulin becomes less effective at lowering blood sugars.
Intermediate Host
A host (animal, insect, snail etc) that harbours a parasite only for a short transition period, during which (usually) some developmental stage is completed. 

Intervertebral Disc
A small disc of material sitting between each vertebrae in the spine.  These act as cushions, with a soft centre surrounded by fibrous material.  If the fibrous material is damaged, the disc material may protrude into the spinal cord, putting pressure on the nerves of the spine and causing paralysis.
The portion of the gastrointestinal tract extending from the stomach to the anus. It is usually divided into two segments, the small intestine and the large intestine.
Inside the cell.
Inside the cranial cavity or head.
Into the muscle.  Generally relates to the site an injection is given.

Into the nose.  This is an effective way of vaccinating dogs against canine cough.
Into the vein.  Generally relates to the site of injection of drugs or fluids.
A serious disorder in which part of the intestine slides, or telescopes, into another part of the intestine. This often blocks the intestine, preventing food or fluid from passing through.
The coloured portion of the eye is called the iris. In the centre of the iris is the black opening called the pupil.


Also called icterus, meaning that a yellow pigment is found in the blood and in the tissues. It is most easily seen in the gums and the whites of eyes.  It can be caused by destruction of red blood cells, liver disease and obstruction of the bile duct.
The second part of the small intestine. The jejunum extends from the duodenum (first part of the small intestine) to the ileum (the final part of the small intestine).
Pertaining to the neck. The jugular veins carry deoxygenated blood from the head back to the heart.  This is a common vein to use for taking blood samples.


Keratitis is inflammation of the cornea (the clear part of the eye). The cornea becomes cloudy, resulting in loss of transparency. All types of keratitis must be treated by a veterinarian.
Keratoconjunctivitis Sicca
Also known as dry eye, is a condition that results from the inadequate production of tears.  This requires veterinary treatment, or it will lead to multiple corneal ulcers and pain in the eyes.

A life-threatening condition associated with uncontrolled diabetes.
Killed Vaccine
Also known as inactivated vaccines. Vaccines which are made by taking the real, disease-causing viruses (or bacteria), killing them, and putting them into a liquid base.


The secretion of milk from the mammary gland and the period of time that a mother lactates to feed her young.
Large Intestine
The portion of the intestine that connects the small intestine to the anus. The large intestine is made up of the caecum, colon and rectum.
Larva (plural larvae)
A distinct juvenile form many animals (such as insects or parasites) undergo before metamorphosis into adults.
Also known as the voice box, it is located at the entrance to the trachea (or windpipe).  The larynx acts to control the flow of air to the trachea and food and water to the oesophagus.
A dormant stage of disease occurring between exposure to a disease-causing agent and the onset of the disease.

Lens Luxation

A condition in which the lens falls out of its normal position in the eye.  The lens can either fall forward through the iris, or backwards into the large area of the back of the eye. 

A lack of energy, motivation, or normal interests.

A large organ in the front of the abdomen that is responsible for the detoxification of blood, and the production of certain digestive enzymes and bile.


Dislocation, usually of a joint.
Lymph Nodes
Are small glands composed of white blood cells called lymphocytes. Lymphocytes play a critical role in the immune system by destroying infectious agents (such as viruses and bacteria) and producing antibodies.


Malabsorption Syndrome
Defined as an animal’s inability to absorb the vitamins, minerals, and other nutrients it needs from food.
Tending to become worse and even result in death. Malignant tumours are cancerous growths which expand quickly and can metastasise, or spread to other areas of the body.

A condition that results from taking an unbalanced diet in which certain nutrients are lacking, in excess, or in the wrong proportions.

Pertaining to the mammary gland or breast tissue.
The lower jaw.

Any of several skin diseases of mammals caused by parasitic mites that burrow into the skin or hair follicles.  It is characterised by skin lesions, itching and loss of hair.
Mast Cell Tumour
Mast cell tumours are cancerous proliferations of mast cells that can spread throughout the body. These tumours are the most frequently recognised malignant or potentially malignant tumours of dogs. They may develop anywhere on the body surface as well as in internal organs. Mast cell tumours have varying appearances ranging from a wart-like nodule to an ulcerated mass to a small lump.
Mastication or chewing is the process by which food is crushed and ground by teeth.

Refers to swelling, inflammation, and infection of the mammary glands.
Maternal Antibody
Antibodies acquired by a newborn animal via the placenta or colostrum (antibody-rich milk) of the mother.
A functional disorder that is defined as dilation of the colon or large intestine. This leads to infrequent and difficult passage of faeces and constipation.
Darkening of the faeces by digested blood pigments. Typically the faeces look black in colour.
The long bones in the front foot connecting the toes to the bones of the wrist (carpus).
The spread of disease from one area of the body to another.  Normally used in the context of a cancerous tumour spreading via the bloodstream or lymphatic system.
The long bones in the back foot connecting the toes to the bones of the ankle (tarsus).
The larval form of some parasitic worms. For example heartworm microfilariae circulate in the bloodstream of infected dogs.
A microscopic, single-celled organism. Microorganisms include bacteria, fungi and viruses.
Modified Live Vaccine
A vaccine that utilises a live, attenuated (weakened) bacteria or virus to elicit an immune response.

Medications capable of breaking down or reducing the viscosity of mucus.  Sometimes used in cases where mucus builds up in the lungs.
Thin layer of tissue lining cavities that are exposed to the external environment and internal environment (such as the mouth, urinary bladder, eyelids). Also known as mucous membranes.
Mucous Membranes
Thin layer of tissue lining cavities that are exposed to the external environment and internal environment (such as the mouth, urinary bladder, eyelids).  Also known as mucosa.
Pertaining to the muscles and skeleton (bones).
Myasthenia Gravis
Is a neuromuscular disease in which severe muscle weakness, made worse with exercise, is the primary sign. It is caused by an inability of certain nerve receptors to function properly.
Large or dilated pupil size.
Radiograph (x-ray) of the spinal cord taken after a radio-opaque dye has been injected into the space around the spinal cord.
Muscle of the heart.


To convert a liquid into a spray for inhalational treatments.
Also known as an autopsy or post-mortem examination.  It refers to the examination of an animal after death, usually to try to determine the cause of death or the cause of previous illness.
Is the premature death of cells and living biological tissue.
Also known as roundworms.
A class of disease in which a group of cells display uncontrolled growth, invasion that intrudes upon and destroys adjacent tissues, and sometimes spreads to other locations in the body. Can be used to describe malignant or benign tumours.
A condition involving a dysfunction of the nerves.
Also known as desexing.  It involves the surgical removal of the testes in males or the ovaries and uterus in females.
Nodules are solid lumps or bumps found on or in an animal's skin.
Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)
Medications with anti-inflammatory, analgesic (pain reducing) and anti-pyretic (fever-reducing) effects. Non-steroidal distinguishes NSAIDs from other drugs which contain steroids, which are also anti-inflammatory.
Non-core Vaccine
Vaccines that should be administered to animals assessed to be at risk of that disease.  For example leptospirosis and canine cough in dogs or feline leukaemia and FIV in cats.
Not capable of causing disease.
A term combining the words “nutrition” and “pharmaceutical”. It is used to describe a food or part of a food that allegedly provides medicinal or health benefits.

Any substance which has nutritious qualities.
A term describe involuntary flicking eye movement. Nystagmus can be horizontal, vertical or rotary (round in semi-circles).


Obsessive Compulsive
A behavioural condition in which a pet repeatedly performs an action out of context.
Refers to a structure or process that is hidden or detected indirectly.
Pertaining to the eye.
The medical term for fluid retention in the body, causing swelling to occur in the affected area.
The part of the intestinal tract between the mouth and stomach.
Off Label
Refers to a drug prescribed to treat a condition or for use in a species or animal for which it has not been approved. Off-label use of a drug must be determined by the attending veterinarian, on consideration of the benefits versus the risks.
A synthetic narcotic that resembles naturally occurring opium.
Term to describe an infection of the bone or bone marrow.
Relating to the ear.
Damaging to the structures of the ear.
The release of an egg from the ovary of the female
A hormone that stimulates the uterus to contract during birth and the mammary glands to release milk.


Packed Cell Volume (PCV)
The volume of blood cells in a sample of blood after it has been centrifuged  The PCV, or haematocrit, is expressed as a percentage. For example, normal for dogs is 40-59% and for cats is 29-50%.
Acceptable to the taste; readily eaten.
The act of feeling with the hand or fingers. A phase of the physical examination in which the sense of touch is used to gather information essential for diagnosis.
A term that describes inflammation of the pancreas. Clinical signs include vomiting, lethargy and a painful abdomen.  May be caused by a fatty meal.
Also known as chronic superficial keratitis, it is an inflammatory condition of the cornea in which blood vessels grow across the surface.
A small solid bump rising from the skin that is usually less than 1 centimetre in diameter.
Refers to loss of motor function due to impairment of muscles or nerves.
A substance used to destroy parasites.
Refers to the administration of a drug into the body through some way other than the digestive tract, such as subcutaneous (under the skin) or intravenous (into a vein) injection.
Refers to partial loss of motor function due to impairment of muscles or nerves.
Term used to describe delivery of a baby or giving birth.
Passive Immunity
Is the transfer of antibodies from one individual to another. It can occur naturally, when maternal antibodies are transferred to the newborn animal in colostrum, and can also be transferred artificially, such as a plasma transfusion.
Causing disease.  Usually used to describe bacteria which are capable of causing disease.
Person who specialises in the diagnosis of diseases through the examination of animal tissue and body fluids.
PCV (Packed Cell Volume)
The volume of blood cells in a sample of blood after it has been centrifuged. The PCV, or haematocrit, is expressed as a percentage. For example, normal for dogs is 40-59% and for cats is 29-50%. 

Per Os
Meaning to give by mouth.
Perianal Fistula
A painful condition of the skin surrounding the anus, in which small tracts open up, bleed and get infected. 
The region of the body between the genitals and the anus.
A thin membrane that lines the abdominal and pelvic cavities, and covers most abdominal organs.
Inflammation of the peritoneum.
The bones that are in the toes.
Chemicals released by an animal enabling it to communicate with other members of its own species. 
Some pheromones are now used as part of anxiety treatment to create a safe area for the animal.
Refers to an increase in the reactivity of the skin to sunlight. It can cause reddening and blistering of the skin.
A pattern of eating non-food materials (such as dirt or rocks).
A dummy medication or treatment.  Used in medication trials to ensure results are accurate and not based on the expectation of an improvement.
A biofilm that develops naturally on the teeth. It is formed by colonising bacteria trying to attach itself to the smooth surface of a tooth.  If plaque is not cleaned off the teeth, it can harden and calcify into tartar.


The liquid portion of blood, including the clotting factors that are not present in serum.  This is often used in transfusions when the clotting of the patient's blood is compromised, such as in rat bait poisoning.

Are found in the blood of animals and functions to promote blood clotting. Also known as thrombocytes. 

Infection or inflammation of the paws and toes.
The term means inflammation of more than one joint. Often used in the context of infectious or immune-mediated diseases.

Having more than the normal number of toes.
Excessive thirst and drinking.
An abnormal growth of tissue projecting from a mucous membrane.

Excessive appetite and eating.
Excessive production of urine.
After surgery or an operation.
The fold of skin that covers the penis.
A hormone produced by the ovaries which is responsible for the continuation of pregnancy and a myriad of other functions.
The forecasted outcome of a disease process or treatment.
Prolapsed Rectum
Describes a medical condition where part of the rectum protrudes through the anus.
Any of a large group of single-celled organisms that live in water or as parasites. Examples include Giardia and Coccidia species.
Relating to, resembling, or characteristic of parrots.
Pertaining to the lungs.
Pulmonary Artery
The artery that carries blood with low levels of oxygen from the heart to the lungs.
Pulmonary Oedema
The accumulation of fluid in the lungs.  Seen in heart failure and other diseases affecting the heart and lungs.

A small lump in the skin filled with pus.
A bacterial infection of the skin.
An accumulation of pus within the uterus.  This is a serious, life-threatening condition.


A fever.

A breeding female cat.


A branch of veterinary science dealing with the medical use of X-rays to diagnose and treat disease.
Lying down.
Expelling food from the oesophagus.  This is a more passive action than vomiting, but easily confused with vomiting.
Pertaining to the kidneys.
Renal Insufficiency
Also called renal failure, is when the kidneys no longer function well enough to maintain a normal state of health.
Pertaining to respiration, the exchange of oxygen and carbon dioxide.
Term referring to the light-sensitive layer of tissue at the back of the inner eye.
Refers to a fungal skin infection that forms small, circular skin lesions.  This can spread to humans, especially children and immuno-compromised individuals.


Sebaceous Glands
Microscopic glands in the skin that secrete an oily or waxy substance.
Separation Anxiety
Is a behavioural condition where dogs, when left alone, exhibit distress and behavioural problems.  Dogs with this condition can become quite destructive in their distress at being left alone.
A toxic state caused by the absorption of pathogenic microorganisms and their products into the bloodstream or tissues.

A toxic state caused by the absorption of pathogenic microorganisms and their products into the bloodstream.
Refers to blood tests that detect the presence of antibodies against an antigen or microorganism.
The clear yellowish fluid obtained upon separating whole blood into its solid and liquid components after it has been allowed to clot.
A term used to describe the release of organisms (bacteria, protozoa, viruses) into the environment from an infected animal.
Skin Cytology
The microscopic examination of cells that have been collected from the skin. 
Skin Scraping
A diagnostic test used in almost every skin condition. The skin is scraped and the material examined under a microscope.
Smooth Muscle
A special type of muscle responsible for the contractility of hollow organs, such as blood vessels, the gastrointestinal tract, the bladder, or the uterus.
Spay (ovariohysterectomy)
Term referring to the surgical removal of the reproductive organs (ovaries and uterus) of the female animal.
A ring of muscle which holds any kind of biological opening closed.
A large abdominal organ with important roles in regard to red blood cells and the immune system.
Refers to the state in which the normal flow of a body liquid stops, for example the flow of intestinal contents through the digestive tract.
Status Epilepticus
A very serious neurological condition in which the brain experiences a prolonged seizure, or a series of prolonged seizures without a full return to consciousness in between.
Also known as a stricture, is an abnormal narrowing in a blood vessel or other tubular or structure, such as the intestine. 

Snoring, usually caused by partial obstruction of the pharynx.

Inflammation of the soft tissues of the mouth, including gingivitis. 
A high-pitched or shrill sound, usually caused by partial obstruction of the nose or layrnx.

Also known as ammonium magnesium phosphate. Struvite can form stones in the urinary bladder. 

Under the skin.
Refers to incomplete or partial dislocation of a joint.
Is the sudden loss of consciousness, or fainting.
Synovial Joint
Is the most movable and widespread type of joint throughout the body. Examples include the knee, elbow and hip.
Pertaining to or affecting the whole body rather than localised.


Refers to a faster than normal resting heart rate.
Refers to a faster than normal resting respiratory, or breathing, rate.
The animal equivalent of an ankle. It is also known as the hock.
A build-up of bacteria, saliva, and food on the teeth which becomes mineralised, forming a hard coating and eventually causing gum disease and possibly tooth loss.
Temporomandibular Joint
The joint where the lower jaw bone, or the mandible, meets the skull.


A life-threatening condition resulting in stiff limbs and muscle spasms.  Caused by a toxin released from bacterial spores within wounds. 
Third Eyelid
A membrane inside the upper and lower eyelids, containing a tear gland.  This membrane comes across the eye as a protection when blinking or if the eye is approached.  It is often more prominant in unwell animals.

The medical term that refers to a low or reduced platelet count.
Is an organised group of cells, not necessarily identical, that together carry out a specific function.
Is a measure of concentration. Normally refers to the level of antibodies in blood to a particular antigen.
To be applied to external body surfaces such as the skin.
A generic term for the presence of toxin in the blood.


The airway passing from the mouth down to the bronchi, also called the windpipe.

Refers to inflammation of the trachea and bronchi.

A tumour is an abnormal growth of body tissue. Tumours can be cancerous (malignant) or non-cancerous (benign).


A defect of the skin, cornea or mucous membrane caused by the loss of damaged tissue.
A technique used to produce an image of a deep structure within the body by directing ultrasound waves at it and recording the reflections (echoes) from it.
Also known as the belly button. The umbilicus is where the umbilical cord attaches to the foetus during pregnancy.
Is a salt derived from uric acid.  Urate can form stones in the urinary bladder.
Is a compound which is essentially the waste produced when the body metabolises protein.
Urinary Incontinence
Is the loss of voluntary control of urination.
Urinary Obstruction
A term to describe one of many different conditions that disrupt normal urine flow from the body. 

Bladder stones.  These are of most concern in males, where they can completely block the passage from the bladder.
Also known as hives. Raised, itchy areas of skin that are usually a sign of an allergic reaction.
Refers to inflammation of the middle layer of the eye.


The administration of a vaccine to stimulate immunity to a disease.
Vaccine Failure
A vaccine failure is when an animal develops a disease in spite of being vaccinated against it. There is usually nothing wrong with the vaccine, but for some reason, the animal's immune system did not adequately respond to it.

Inflammation of blood vessels.
Vasoconstriction is the narrowing (constriction) of blood vessels by muscles in their walls.
Vasodilation is the widening (dilation) of blood vessels by the relaxation of the muscles in their walls.
Vena Cava
The cranial vena cava is the large vein which returns blood to the heart from the head, neck and both upper limbs. The caudal vena cava returns blood to the heart from the lower part of the body.
The large, muscular chambers of the heart that pump blood to the body or lungs.
Vestibular System
Is the system comprised of the inner ear, nerves and brain, that provides a sense of balance.
A small infectious agent that is unable to replicate outside a living animal cell.  Since they live inside normal cells, they are much harder to treat than bacteria.
Abnormal twisting of the intestines or stomach. This can be a life threatening condition due to the loss of blood supply and accumulation of toxic gases and fluids in the portion of the obstructed bowel segment.


The act of a dog giving birth.
White Blood Cells
Are cells of the immune system involved in defending the body against both infectious agents (bacteria, viruses, and fungi) and foreign materials.
Window of Susceptibility

A time period in the life of a young animal in which the maternal antibodies are too low to provide protection against a certain disease, but too high to allow a vaccine to work and produce immunity.


High-energy electromagnetic radiation used to take radiographs.


A term used to describe any disease or infection that is naturally transmissible from animals to humans.