Abdomen
The part of the body between the chest and pelvis that contains the digestive organs – in other words, the belly.

Abscess
A pocket of pus in the body, usually caused by infection. Abscesses are a common result of cat fights.

Acute
Describes something that starts suddenly and is often severe (e.g. an acute infection).

Addison’s Disease
A rare disorder in which the adrenal glands don’t produce enough steroid hormones (corticosteroids). It needs lifelong hormone replacement, with regular check-ups and monitoring.

Alimentary
Relating to food or the digestive tract (the alimentary canal).

Allergen
A substance that can cause an allergic reaction. In allergic animals, the immune system treats it as “foreign” or “dangerous” and reacts. In non-allergic animals it causes no reaction.

Alopecia
Hair loss from the head or body. It has many possible causes, including parasites, hormone imbalances, food allergies and infection – finding the cause is key to treating it.

Analgesia
Pain relief. An analgesic is a medication that relieves pain.

Anaphylaxis
A rapid, serious allergic reaction that affects several parts of the body at once. Severe reactions can be fatal.

Anaemia
A lower than normal number of red blood cells (erythrocytes) carrying oxygen around the body.

Anaesthesia
A complete loss of feeling or sensation, created with medication so surgery or procedures can be done without pain. General anaesthesia affects the whole body; local anaesthesia affects one area.

Anorexia
Loss of appetite, whatever the cause.

Antibiotics
Medications that kill or slow the growth of bacteria. They don’t work against viral infections.

Antibody
Also called an immunoglobulin. A Y-shaped protein the immune system uses to identify and neutralise invaders such as bacteria and viruses.

Antiemetic
A medication used to treat vomiting and nausea.

Antifungal
A medication used to treat fungal infections such as ringworm.

Antigen
A substance that triggers the body to make antibodies. The immune system sees it as a foreign and potentially harmful invader (e.g. bacteria and viruses).

Antipruritic
A medication that relieves itching.

Antipyretic
A medication that reduces a fever or high temperature.

Antitussive
A medication that relieves coughing, often prescribed for conditions that cause severe coughing, such as canine cough.

Anus
The opening at the end of the digestive tract where faeces are passed.

Arrhythmia
An irregular heartbeat. It happens when the electrical signals that coordinate the heart aren’t working properly, so the heart beats too fast, too slow or unevenly.

Articular
Relating to a joint.

Ascites
A build-up of fluid in the abdomen (the peritoneal cavity).

Aspirate
To draw fluid in or out with suction. Aspiration can also mean breathing something into the airway, such as food.

Asymptomatic
When an animal carries a disease or infection but shows no clinical signs.

Ataxia
A lack of coordination of muscle movements, often seen as wobbliness or unsteadiness.

Atopy
A tendency to develop certain allergies. Often used to describe atopic dermatitis, which causes itchy, inflamed skin.

Atrial Fibrillation
An irregular heart rhythm caused by disorganised electrical activity in the heart’s two upper chambers (atria). Instead of contracting properly, the atria quiver, so the lower chambers (ventricles) don’t fill properly before pumping blood to the body.

Atrium
A chamber where blood enters the heart, as opposed to the ventricle, which pumps it out.

Atrophy
A gradual decrease in the size of an organ or tissue.

Attenuated
Weakened. Usually refers to a vaccine where the disease-causing parts have been weakened during manufacture so it is safe to give.

Auscultate
To listen to the sounds of the body during an examination, usually with a stethoscope.

Autoimmune
A condition where an overactive immune system attacks the body’s own normal tissues by mistake.

Azotaemia
Abnormally high levels of waste products such as urea and creatinine in the blood, usually due to kidney problems or dehydration.

Bacterium
A single-celled microorganism and one of the most basic forms of life. Bacteria are everywhere, and some can cause disease in animals.

Benign
Harmless; not cancerous.

Bilateral
Affecting both sides.

Bile
A green-yellow fluid made in the liver that plays a vital role in digesting fats.

Biopsy
Removing a small sample of tissue or cells to check for disease or see how far it has spread.

Bitch
A female dog.

Bladder
A sac that holds liquid until it is passed from the body. Usually refers to the urinary bladder.

Bloat
A serious condition in which the stomach becomes overstretched with gas. It is a major health risk for many deep-chested dogs.

Blood Glucose
The amount of glucose (sugar) in the blood.

Bone Marrow
The spongy, fatty tissue inside some large bones. It contains stem cells that develop into red blood cells, white blood cells and platelets.

Borborygmus
The rumbling noise made by gas moving through the stomach and intestines.

Bradycardia
An abnormally slow heart rate.

Bronchi
The large airways within the lungs.

Bronchodilator
A medication that opens up (dilates) the airways in the lungs.

BUN
Blood urea nitrogen. Measures urea, a waste product from breaking down protein, in the blood. Used to help assess kidney function.

Caecum
Part of the gut between the small and large intestines. In dogs it is a small, coiled organ.

Calcified
Hardened by a build-up of calcium salts in soft tissue.

Calculus
A hard mass of material, usually mineral salts, that forms in an organ. Bladder and kidney stones are examples.

Cancer
A group of diseases where cells grow uncontrollably, invade and destroy nearby tissue, and sometimes spread to other parts of the body. Usually used to describe malignant tumours.

Candida
A yeast normally found in areas such as the mouth, genital tract and intestines. It can cause disease in animals.

Canine
Relating to dogs.

Carcinoma
A type of cancer that starts in epithelial cells – the cells that line internal organs, cavities, glands and skin.

Cardiac
Relating to the heart.

Cardiomyopathy
Literally “heart muscle disease”.

Cardiopulmonary
Relating to both the heart and lungs.

Cardiovascular
The circulatory system – the heart and blood vessels – which carries nutrients and oxygen to the body and removes carbon dioxide and other waste.

Carpus
The animal equivalent of our wrist.

Castration
Surgical removal of the testicles.

Cataract
A cloudy, white area in the lens of the eye. Cataracts are one of the most common eye problems in dogs. Severe cataracts can cause blindness and may point to underlying disease such as diabetes.

Caudal
Towards the tail or the back end of the body.

Central Nervous System (CNS)
The brain and spinal cord.

Cerebellum
The part of the brain that controls movement and coordination.

Cerebrum
The part of the brain that controls emotion, behaviour and learning.

Chemotherapy
Treating cancer with medication. The drugs affect cancer cells more than healthy cells, so the cancer can be treated without causing permanent damage.

Chronic
Describes a disease that develops slowly and lasts a long time (e.g. chronic osteoarthritis).

Cirrhosis
A long-term liver disease in which healthy tissue is replaced by scar tissue.

Coagulation
The process of forming a blood clot (thrombus) to stop bleeding from damaged tissue, blood vessels or organs.

Coagulopathy
A problem with the body’s ability to form blood clots.

Coccidia
Microscopic single-celled organisms that infect animal cells. They can cause watery or bloody diarrhoea in pets.

Colitis
Inflammation of the large intestine (colon).

Colon
The part of the large intestine between the caecum and the rectum.

Colostrum
The antibody-rich milk mothers produce in the first few days after giving birth.

Coma
A state of unconsciousness from which an animal can’t be woken.

Complete Blood Count (CBC)
Also called a full blood count or blood panel. A test that looks at the cells in the blood to assess overall health and detect problems such as anaemia and infection.

Computerised Tomography (CT) Scan
Also called a CAT scan. It combines many X-ray images taken from different angles to create cross-sectional pictures of the bones and soft tissues inside your pet’s body.

Congenital
A condition present from birth.

Conjunctiva
The tissue that lines the inside of the eyelids and covers the white of the eye (sclera).

Conjunctivitis
Inflammation of the conjunctiva.

Constipation
When bowel movements happen less often than normal, or the stools are hard, dry and difficult or painful to pass.

Coprophagia
Eating faeces. It is normal in some species, such as rabbits, but in others it can be linked to disease or behavioural problems.

Core Vaccine
Vaccines that are strongly recommended for every pet – for example, parvovirus in dogs or panleucopenia in cats.

Cornea
The clear front part of the eye.

Corticosteroid
Steroid hormones made by the adrenal glands, or their synthetic equivalents.

Cranial
Relating to the head, or towards the head.

Culture
Growing microorganisms in the lab to diagnose an infection and guide treatment.

Cushing’s Syndrome
A condition where problems with the pituitary or adrenal glands cause the body to release too much cortisone (corticosteroid).

Cutaneous
Relating to or affecting the skin.

Cyanosis
A bluish tinge to the skin and gums caused by too little oxygen in the blood.

Cyst
An abnormal pocket in bone or soft tissue filled with fluid or semi-solid material.

Cystitis
Inflammation of the urinary bladder.

Cytology
Diagnosing disease by examining cells under a microscope.

Dehydration
An excessive loss of water from the body.

Dermal
Relating to the skin.

Dermatitis
Inflammation of the skin.

Diabetes Mellitus
A disease where the body can’t properly use sugar (glucose). It is commonly treated with insulin.

Diagnostic Test
A test to find out whether a disease is present, or what is causing it.

Diarrhoea
Frequent, loose or watery faeces, usually a sign of a gut problem.

Digestive System
The organs that move and process food through the body, including the salivary glands, mouth, oesophagus, stomach, small intestine, liver, gall bladder, pancreas, colon, rectum and anus.

Dilated Cardiomyopathy
A disease where the heart’s chambers become enlarged and the heart muscle weakens, so it can’t pump effectively.

Disinfection
A cleaning process that destroys most microorganisms, but not the most resistant ones.

Distemper
A contagious viral disease of dogs. Signs include loss of appetite, eye and nose discharge, vomiting, fever, lethargy, partial paralysis and sometimes death.

Diuretic
A medication that increases urine production.

Domestic Animal
An animal that isn’t wild and is kept as a pet or to produce food.

Dry Eye
Also known as keratoconjunctivitis sicca (KCS). A condition caused by the eyes not producing enough tears.

Duodenum
The first part of the small intestine, running from the stomach to the jejunum.

Duration of Immunity
How long an animal stays protected from a disease after vaccination. Some vaccines protect for several years; others only for up to a year.

Dysphagia
Difficulty swallowing.

Dysplasia
Abnormal development of tissues.

Dyspnoea
Difficult or laboured breathing; shortness of breath.

Dystocia
A difficult birth.

Dysuria
Painful or difficult urination.

Ear Canal
The narrow tube between the outer ear and the eardrum, through which sound travels.

Ear Drum
The thin membrane separating the outer ear from the middle ear. Also called the tympanic membrane.

Ear Mites
Tiny mites that live in animals’ ears. They are just visible to the naked eye as small white dots.

ECG
An electrocardiogram – a test that records the heart’s electrical activity.

Echocardiogram
An ultrasound of the heart, which uses sound waves to create a moving picture of it.

Ectoparasite
A parasite, such as a flea, that lives on the outside of an animal.

Ectopic
Meaning “out of place” (e.g. an ectopic pregnancy implants outside the uterus).

Electrolyte
Minerals that are essential to life, including sodium, potassium, chloride, calcium and phosphorus.

Elizabethan Collar
A cone-shaped collar that stops an animal biting, licking or scratching wounds while they heal.

Emaciation
A severely wasted, thin body condition.

Emesis
Vomiting.

Encephalitis
Inflammation of the brain.

Encephalopathy
Disease, damage or malfunction of the brain.

Endocrine
Relating to hormones and the glands that produce them. These hormones regulate growth, body function and sexual development.

Endoscope
A thin, lighted instrument used to look inside organs such as the oesophagus, stomach or airways.

Endotracheal Tube
A breathing tube placed in the windpipe (trachea), commonly used during anaesthesia to deliver oxygen and anaesthetic gas to the lungs.

Enteritis
Inflammation of the intestine, especially the small intestine.

Envenomation
Injection of venom through a sting, spine or bite.

Enzyme
A protein that speeds up chemical reactions. Almost every process in a cell relies on enzymes.

Epidermis
The outer layer of the skin.

Epistaxis
A nosebleed.

Erythema
Redness of the skin caused by widened blood vessels, usually due to irritation or injury.

Erythrocyte
A red blood cell.

Faeces
Waste from digested food passed through the anus; also called stool.

Feline
Relating to cats.

Fine Needle Aspirate
A test used to investigate lumps just under the skin. A thin needle collects cells from the lump, which are then stained and examined under a microscope.

FIV (Feline Immunodeficiency Virus)
A virus that infects cats only (not people), spread mainly through bites during fights. It causes feline AIDS – a gradual weakening of the immune system that makes it harder for cats to fight off other infections.

Flatulence
Excessive gas in the gut.

FLUTD (Feline Lower Urinary Tract Disease)
A group of conditions affecting the bladder and/or urethra of cats. Common signs include straining to urinate and blood in the urine.

Foetus
An unborn animal in the later stages of development.

Follicle
A small cavity or narrow pocket (e.g. a hair follicle).

Foreign Body
Anything in the body that shouldn’t be there – for example, a splinter or glass under the skin, or a toy, ball or bone in the gut.

Fracture
A break in bone or other hard tissue, caused by trauma or bone disease.

Gait
The way an animal walks or moves. Assessed to help find the cause of lameness.

Gastric
Relating to the stomach.

Gastritis
Inflammation of the stomach lining.

Gastrointestinal
Relating to the stomach and intestines.

Gestation
Pregnancy – the period of carrying an embryo or foetus.

Gingival
Relating to the gums.

Gingivitis
Inflammation of the gums.

Glaucoma
An eye disease caused by increased pressure inside the eyeball. It can damage the optic nerve and lead to gradual loss of vision.

Glucosuria
Glucose in the urine. Normally the kidneys return glucose to the bloodstream, so urine shouldn’t contain any.

Granuloma
A lump or nodule of chronically inflamed tissue.

Haemangiosarcoma
A malignant tumour of the blood vessels, usually found in the skin, liver or spleen.

Haematocrit
See Packed Cell Volume (PCV).

Haematology
The study of blood and blood diseases.

Haematoma
A blood-filled swelling outside the blood vessels, usually caused by bleeding.

Haematuria
Blood in the urine; often a sign of urinary tract disease.

Haemorrhage
Bleeding.

Heartworm
A parasite (Dirofilaria immitis) spread by mosquito bites. Dogs are the main host, but cats and ferrets can also be infected. The worms live in the heart and can cause blockages and thickening of the heart and nearby blood vessels.

Hepatic
Relating to the liver.

Hepatitis
Inflammation of the liver.

Hepatomegaly
An abnormally enlarged liver.

Hernia
When an organ pushes through the wall of the cavity that normally holds it.

Hormone
A chemical messenger released by a cell or gland that affects cells in other parts of the body.

Host
A living animal that a parasite lives on or in.

Hybrid
The offspring of two animals of different breeds, varieties or species.

Hydrocephalus
An abnormal build-up of fluid (cerebrospinal fluid) in the skull. It can increase pressure on the brain, enlarge the head, and cause brain damage or death.

Hyper-
A prefix meaning more than normal.

Hyperglycaemia
High blood glucose (sugar).

Hyperplasia
An abnormal increase in the number of cells in a tissue or organ.

Hypersensitivity
An allergic over-reaction to a substance, such as a bee sting or medication.

Hypertension
High blood pressure.

Hyperthermia
A raised body temperature.

Hyperthyroidism
An overactive thyroid gland producing too much thyroid hormone. More common in cats.

Hypertrophy
Enlargement of an organ or tissue because its cells get bigger (rather than more numerous, as in hyperplasia).

Hyperventilate
To breathe excessively fast and hard, upsetting the balance of gases in the blood.

Hypo-
A prefix meaning less than normal.

Hypoglycaemia
Low blood glucose (sugar).

Hypoplasia
Incomplete development of an organ or structure.

Hypotension
Low blood pressure.

Hypothermia
An abnormally low body temperature.

Hypothyroidism
An underactive thyroid gland producing too little thyroid hormone. More common in dogs.

Hypoxia
Not enough oxygen reaching the body’s tissues.

Icterus
See Jaundice.

IDDM
Insulin-dependent diabetes mellitus – a form of diabetes where the body makes little or no insulin, so the animal relies on insulin injections.

Idiopathic
A disease with no known cause.

Ileus
When the gut stops moving food along normally.

Immune System
The body’s defence system against foreign substances, cells and infections.

Immune-Mediated
Conditions caused by the immune system acting abnormally. For example, in immune-mediated haemolytic anaemia (IMHA), the immune system destroys the body’s own red blood cells.

Immunisation
Creating immunity against a disease, usually through vaccination. A vaccinated animal isn’t always immune – if the body doesn’t respond properly, or the vaccine isn’t given correctly, immunity may not develop.

Immunity
When the immune system is primed to protect the body against a specific disease-causing agent, such as a virus or bacteria.

Immunodeficiency
When the immune system is weakened and less able to fight infection. Can be caused by viruses such as FIV in cats.

Immunosuppressive
Something that suppresses the immune system.

Inactivated Vaccine
A vaccine made from real disease-causing viruses or bacteria that have been killed. Also called a killed vaccine.

Incontinence
Loss of control over urination or bowel movements.

Incubation Period
The time between infection and the first signs of disease.

Infection
When microorganisms such as bacteria or viruses invade the body and cause disease.

Infestation
Being invaded or overrun by parasites.

Inflammation
The body’s local response to injury – redness, heat, pain, swelling and often loss of function.

Inherited
Passed down genetically through families.

Innate
Present from birth; a permanent characteristic.

Insulin
A hormone made by the pancreas that controls blood glucose.

Insulin Resistance
When insulin becomes less effective at lowering blood sugar.

Intermediate Host
An animal, insect, snail or other host that carries a parasite for a short time while it goes through a stage of development.

Intestine
The part of the gut from the stomach to the anus, made up of the small and large intestines.

Intracellular
Inside a cell.

Intracranial
Inside the skull.

Intramuscular
Into the muscle – usually describes where an injection is given.

Intranasal
Into the nose. An effective way to vaccinate dogs against canine cough.

Intravenous
Into a vein – usually describes how medication or fluids are given.

Intussusception
A serious condition where part of the intestine slides (telescopes) into the next section, often causing a blockage.

Iris
The coloured part of the eye. The black opening in its centre is the pupil.

Jaundice
Also called icterus. A yellow colour in the skin, gums and whites of the eyes caused by high levels of bilirubin in the blood. It can be caused by red blood cell destruction, liver disease or a blocked bile duct.

Jejunum
The middle section of the small intestine, between the duodenum and the ileum.

Jugular
Relating to the neck. The jugular veins carry blood from the head back to the heart.

Keratitis
Inflammation of the cornea (the clear front of the eye), making it cloudy. All types of keratitis need veterinary treatment.

Keratoconjunctivitis Sicca
See Dry Eye.

Ketoacidosis
A life-threatening complication of uncontrolled diabetes.

Killed Vaccine
See Inactivated Vaccine.

Lactation
Producing milk from the mammary glands, and the period a mother feeds her young.

Large Intestine
The part of the gut connecting the small intestine to the anus, made up of the caecum, colon and rectum.

Larva (plural larvae)
The juvenile form many insects and parasites go through before becoming adults.

Larynx
The voice box, at the entrance to the windpipe (trachea). It directs air into the windpipe and food and water into the oesophagus.

Latent
A dormant stage between exposure to a disease-causing agent and the start of illness.

Liver
A large organ at the front of the abdomen that detoxifies the blood and produces bile and certain digestive enzymes.

Lymph Nodes
Small glands made up of white blood cells called lymphocytes, which destroy infections (such as viruses and bacteria) and make antibodies.

Malabsorption Syndrome
When an animal can’t absorb the vitamins, minerals and other nutrients it needs from food.

Malignant
Cancerous. Malignant tumours can grow quickly and spread (metastasise) to other parts of the body.

Malnutrition
A condition caused by an unbalanced diet – where nutrients are lacking, in excess or in the wrong proportions.

Mammary
Relating to the mammary glands (breast tissue).

Mandible
The lower jaw.

Mange
A skin disease caused by parasitic mites that burrow into the skin or hair follicles, causing sores, itching and hair loss.

Mast Cell Tumour
A cancer of mast cells and the most common malignant (or potentially malignant) tumour in dogs. They can appear anywhere on the skin or in internal organs, and range from a wart-like lump to an ulcerated mass.

Masticate
To chew – crushing and grinding food with the teeth.

Mastitis
Swelling, inflammation and infection of the mammary glands.

Maternal Antibody
Antibodies a newborn receives from its mother, through the placenta or colostrum.

Megacolon
An enlarged, stretched colon, leading to infrequent, difficult bowel movements and constipation.

Melaena
Black, tarry faeces caused by digested blood.

Metacarpus
The long bones in the front foot connecting the toes to the wrist (carpus).

Metastasis
The spread of disease, usually cancer, from one part of the body to another through the bloodstream or lymphatic system.

Metatarsus
The long bones in the back foot connecting the toes to the ankle (tarsus).

Microfilaria
The larval form of some parasitic worms. For example, heartworm microfilariae circulate in the blood of infected dogs.

Microorganism
A microscopic organism, such as bacteria, fungi and viruses.

Modified Live Vaccine
A vaccine that uses a live but weakened (attenuated) bacteria or virus to trigger an immune response.

Mucolytic
A medication that breaks down or thins mucus.

Mucous Membranes
Also called mucosa. The thin, moist tissue lining areas such as the mouth, eyelids and bladder.

Musculoskeletal
Relating to the muscles and skeleton.

Myasthenia Gravis
A neuromuscular disease causing severe muscle weakness, caused by certain nerve receptors not working properly.

Mydriasis
Large or dilated pupils.

Myelogram
An X-ray of the spinal cord taken after a special dye is injected around it.

Myocardium
The heart muscle.

Nebulise
To turn liquid medication into a fine mist that can be breathed in.

Necropsy
An examination of an animal after death; also known as an autopsy or post-mortem.

Necrosis
The premature death of cells and living tissue.

Nematodes
Roundworms.

Neoplasia
Uncontrolled growth of cells that can invade nearby tissue and sometimes spread. Can describe both malignant and benign tumours.

Neuropathy
A condition where the nerves don’t work properly.

Neuter
Also known as desexing. Surgical removal of the testes in males, or the ovaries and uterus in females.

Nodule
A solid lump or bump on the skin.

Non-core Vaccine
Vaccines given to animals at risk of a particular disease – for example, leptospirosis and canine cough in dogs, or feline leukaemia and FIV in cats.

Non-pathogenic
Not able to cause disease.

NSAIDs (Non-Steroidal Anti-Inflammatory Drugs)
Medications that reduce inflammation, pain and fever without containing steroids.

Nutraceutical
A blend of “nutrition” and “pharmaceutical” – a food or food ingredient said to have health or medicinal benefits.

Nutrient
Any substance that provides nourishment.

Nystagmus
Involuntary eye movement, which can be side to side, up and down, or rotating.

Obsessive Compulsive
A behavioural condition where a pet repeats an action over and over, out of context.

Occult
Hidden, or only detected indirectly.

Ocular
Relating to the eye.

Oedema
Fluid retention in the body, causing swelling in the affected area.

Oesophagus
The tube connecting the mouth to the stomach.

Off Label
Using a medication for a condition it hasn’t been officially approved for. This decision must be made by the treating veterinarian.

Opioid
A strong pain-relief medication related to opium.

Osteomyelitis
An infection of the bone or bone marrow.

Otic
Relating to the ear.

Ototoxic
Damaging to the structures of the ear.

Ovulate
To release an egg from the ovary.

Oxytocin
A hormone that makes the uterus contract during birth and the mammary glands release milk.

Packed Cell Volume (PCV)
Also called haematocrit. The percentage of red blood cells in a blood sample after it has been spun at high speed. Normal is around 40–59% for dogs and 29–50% for cats.

Palatable
Tasty; readily eaten.

Palpation
Feeling with the hands or fingers during a physical examination to help with diagnosis.

Pancreatitis
Inflammation of the pancreas. Signs include vomiting, lethargy and a painful abdomen.

Pannus
Also called chronic superficial keratitis. An inflammatory condition where blood vessels grow across the surface of the cornea.

Papule
A small, solid raised bump on the skin, usually less than 1 cm across.

Paralysis
Loss of movement due to a problem with the muscles or nerves.

Parasiticide
A product that kills parasites.

Parenteral
Giving medication by a route other than the digestive tract, such as an injection under the skin or into a vein.

Paresis
Partial loss of movement due to a problem with the muscles or nerves.

Parturition
Giving birth.

Passive Immunity
Antibodies passed from one animal to another – naturally, from mother to newborn through colostrum, or artificially, such as through a plasma transfusion.

Pathogenic
Able to cause disease. Usually describes bacteria.

Pathologist
A specialist who diagnoses disease by examining tissue and body fluids.

PCV
See Packed Cell Volume (PCV).

Perianal Fistula
A painful condition where small tracts open up in the skin around the anus, bleed and become infected.

Perineal
The area between the genitals and the anus.

Peritoneum
A thin membrane lining the abdominal and pelvic cavities and covering most abdominal organs.

Peritonitis
Inflammation of the peritoneum.

Phalanges
The bones of the toes.

Pheromone
A chemical released by an animal to communicate with others of its species.

Photosensitivity
Increased sensitivity of the skin to sunlight, which can cause redness and blistering.

Pica
Eating non-food items, such as dirt or rocks.

Placebo
A dummy medication or treatment.

Plaque
A film of bacteria that naturally builds up on the teeth.

Platelets
Also called thrombocytes. Cells in the blood that help it clot.

Polyarthritis
Inflammation of more than one joint, often linked to infectious or immune-mediated disease.

Polydactyl
Having more toes than normal.

Polydipsia
Excessive thirst and drinking.

Polyp
An abnormal growth projecting from a mucous membrane.

Polyphagia
Excessive appetite and eating.

Polyuria
Producing excessive amounts of urine.

Postoperative
After surgery.

Prepuce
The fold of skin covering the penis.

Progesterone
A hormone made by the ovaries that maintains pregnancy, among many other roles.

Prognosis
The expected outcome of a disease or treatment.

Prolapsed Rectum
When part of the rectum pushes out through the anus.

Protozoa
Single-celled organisms that live in water or as parasites, such as Giardia and Coccidia.

Pruritus
Itchiness.

Psittacine
Relating to parrots.

Pulmonary
Relating to the lungs.

Pulmonary Arteries
The arteries that carry low-oxygen blood from the heart to the lungs.

Pulmonary Oedema
A build-up of fluid in the lungs.

Pustule
A small, pus-filled lump in the skin.

Pyoderma
A bacterial skin infection.

Pyometra
A build-up of pus in the uterus.

Queen
A breeding female cat.

Radiology
The use of X-rays and other imaging to diagnose and treat disease.

Recumbency
Lying down.

Regurgitation
Bringing food back up from the oesophagus (different from vomiting).

Renal
Relating to the kidneys.

Renal Insufficiency
Also called kidney failure. When the kidneys can no longer work well enough to keep the body healthy.

Respiratory
Relating to breathing – the exchange of oxygen and carbon dioxide.

Retina
The light-sensitive layer of tissue at the back of the eye.

Ringworm
A fungal skin infection.

Sebaceous Glands
Tiny glands in the skin that produce an oily, waxy substance.

Separation Anxiety
A behavioural condition where dogs become distressed and show problem behaviours when left alone.

Sepsis
A dangerous condition caused by disease-causing microorganisms and their toxins entering the bloodstream or tissues.

Septicaemia
Blood poisoning – when disease-causing microorganisms and their toxins enter the bloodstream.

Serology
Blood tests that detect antibodies against a particular antigen or microorganism.

Serum
The clear, yellowish fluid left after blood has clotted and been separated.

Shedding
When an infected animal releases organisms (bacteria, protozoa, viruses) into the environment.

Skin Cytology
Examining cells collected from the skin under a microscope.

Skin Scraping
A common test for skin conditions – the skin is gently scraped and the material examined under a microscope.

Smooth Muscle
The type of muscle that controls hollow organs such as blood vessels, the gut, bladder and uterus.

Spay (Ovariohysterectomy)
Surgical removal of the ovaries and uterus in a female animal.

Sphincter
A ring of muscle that keeps a body opening closed.

Spleen
A large abdominal organ with important roles in red blood cells and the immune system.

Stasis
When the normal flow of a body fluid stops – for example, gut contents not moving through the digestive tract.

Status Epilepticus
A very serious condition involving a prolonged seizure, or repeated seizures without full recovery of consciousness in between.

Stenosis
Also called a stricture. An abnormal narrowing of a blood vessel or other tube-like structure, such as the intestine.

Struvite
Also called ammonium magnesium phosphate. A mineral that can form stones in the bladder.

Subcutaneous
Under the skin.

Subluxation
A partial dislocation of a joint.

Syncope
A sudden loss of consciousness; fainting.

Synovial Joint
The most common and most movable type of joint, such as the knee, elbow and hip.

Systemic
Affecting the whole body rather than one area.

Tachycardia
A faster than normal resting heart rate.

Tachypnoea
A faster than normal resting breathing rate.

Tarsus
The animal equivalent of an ankle, also known as the hock.

Tartar
A hard, mineralised build-up of bacteria, saliva and food on the teeth. It can lead to gum disease and tooth loss.

Temporomandibular Joint
The joint where the lower jaw (mandible) meets the skull.

Thrombocytopaenia
A low platelet count.

Tissue
A group of cells that work together to perform a specific function.

Titre
A measure of concentration – usually the level of antibodies in the blood against a particular disease.

Topical
Applied to the outside of the body, such as the skin.

Toxaemia
Toxins in the blood.

Tracheobronchitis
Inflammation of the windpipe (trachea) and airways (bronchi).

Tumour
An abnormal growth of tissue. Tumours can be cancerous (malignant) or non-cancerous (benign).

Ulcer
A sore on the skin, cornea or a mucous membrane where damaged tissue has been lost.

Ultrasound
An imaging technique that uses sound waves and their echoes to create pictures of structures inside the body.

Umbilicus
The belly button – where the umbilical cord attached during pregnancy.

Urate
A salt formed from uric acid. Urates can form stones in the bladder.

Urea
A waste product made when the body breaks down protein.

Urinary Incontinence
Loss of voluntary control over urination.

Urinary Obstruction
Any condition that blocks the normal flow of urine out of the body.

Urticaria
Hives – raised, itchy patches of skin, usually a sign of an allergic reaction.

Uveitis
Inflammation of the middle layer of the eye.

Vaccination
Giving a vaccine to build immunity against a disease.

Vaccine Failure
When an animal gets a disease despite being vaccinated. Usually nothing is wrong with the vaccine – the animal’s immune system just didn’t respond well enough.

Vasculitis
Inflammation of the blood vessels.

Vasoconstriction
Narrowing of the blood vessels as the muscles in their walls tighten.

Vasodilation
Widening of the blood vessels as the muscles in their walls relax.

Vena Cava
The large veins that return blood to the heart. The cranial vena cava carries blood from the head, neck and front legs; the caudal vena cava from the rest of the body.

Ventricle
The large, muscular chambers of the heart that pump blood to the body or lungs.

Vestibular System
The inner ear, nerves and brain working together to provide balance.

Virus
A tiny infectious agent that can only multiply inside living cells.

Volvulus
An abnormal twisting of the stomach or intestines. It can be life-threatening because blood supply is cut off and gas and fluid build up.

Whelping
A dog giving birth.

White Blood Cells
Immune cells that defend the body against infections (bacteria, viruses and fungi) and foreign material.

Window of Susceptibility
A period in a young animal’s life when maternal antibodies are too low to protect against disease, but still high enough to stop a vaccine from working.

X-ray
High-energy radiation used to take images (radiographs) of the inside of the body.

Zoonotic
A disease or infection that can be passed from animals to people.