Acanthosis nigricans = A cutaneous reaction characterised by skin thickening, alopecia and excessive pigmentation. The cause may be due to friction, allergy or a hormone imbalance.

Addison's disease = See hypoadrenocorticism.

Alopecia = The loss of hair from any site and for any reason.

Anaemia = Deficiency of quality or quantity of red corpuscles in the blood.

Antitussive = An agent that suppresses coughing.

Anuria = Cessation of the secretion of urine.

Aortic stenosis = Narrowing of the aorta.

Apnoea = Cessation of breathing.

Arthritis = Inflammation of one or more joints.

Ascites = Free fluid in the peritoneal cavity.

Atopy = A state of hypersensitivity to certain antigens.

Aura = The premonition that often precedes an epileptic fit.

Aural haematoma = A blood filled swelling of the pinna (usually secondary to trauma/head shaking as a result of an ear infection).

Auroscope = An instrument used to examine the inside of the ears; also known as an otoscope.

Azotaemia = Excessive nitrogen containing compounds in the blood.

Blepharitis = Inflammation of the eyelids.

Blepharospasm = Spasm of the obicularis muscle of the eyelid, often the result of a foreign body or corneal injury.

Bradypnoea = Lowered respiratory rate.

Bulla osteotomy = Removal of the tympanic bulla in order to drain the middle ear in cases of otitis media.

Bursitis = Inflammation of the bursa.

Cachexia = Accelerated starvation; extreme debility and emancipation; typical of the late stage of serious disease.

Cardiomyopathy = A chronic disorder of the heart muscle.

Cellulitis = A diffuse inflammation of connective tissue, especially of subcutaneous tissue.

Chorioretinitis = An inflammatory condition of both the choroid and the retina of the eye.

Chylothorax = The presence of effused chyle in the pleural cavity.

Clonic = The second stage of a grand mal fit.

Colitis = Inflammation of the colon.

Conjunctivitis = Inflammation of the conjunctiva.

Corneal oedema = Excessive accumulation of fluid within the cornea.

Corneal pannus = Chronic progressive keratitis and vascularisation of the cornea.

Corneal sequestrum = An avascular response to corneal injury.

Cushing's disease = See hyperadrenocorticism.

Cyanosis = A bluish appearance of the mucous membranes caused by imperfect oxygenation of the blood; indicative of circulatory failure and is common in respiratory diseases.

Cystitis = Inflammation of the urinary bladder.

Dermatitis = Inflammation of the skin.

Diabetes insipidus = A disease that arises as a result of posterior pituitary dysfunction; characterised by an increased flow of urine of a low specific gravity and polydipsia.

Diabetes mellitus = A disturbance in the oxygenation and utilisation of glucose, which is secondary to the malfunction of the beta cells of the pancreas, whose function is the production and release of insulin.

Distichiasis = A row of eyelashes turned against the eyelid that cause irritation.

Diuresis = Increased excretion of urine.

DJD = Degenerative joint disease; a progressive condition that leads to the erosion of cartilage and the formation of new bone deposits around the joints.

Dry eye = See Keratoconjunctivitis sicca (KCS).

Dyspnoea = Difficulty breathing.

Dysuria = Difficult or painful micturition (urination).

Ectopic = Located away from the normal anatomic position.

Ectropion = An outwardly turning eyelid margin.

Endocardiosis = Progressive degeneration of the cardiac atrioventricular valves.

Endocarditis = Inflammation of the lining membrane and muscles of the heart.

Enophthalmos = A condition in which the eyeball is abnormally sunken into its socket.

Entropion = An inwardly turning eyelid margin.

EPI = Exocrine pancreatic insufficiency; dysfunction of the exocrine pancreas as a result of atrophy of the acinar cells or from chronic pancreatitis.

Erythema = Redness of the skin caused by congestion of the capillaries in its lower layers.

Excoriation = An abrasion of the skin; often as a result of self-inflicted trauma following conditions such as flea allergy dermatitis.

Expectorant = A remedy which facilitates the coughing up of sputum.

Epiphora = Excessive lacrimation.

Epistaxis = Nose bleed.

Gastritis = Inflammation of the lining of the stomach.

Glaucoma = Raised intraocular pressure.

Glomerulonephritis = Inflammation of the glomeruli of the kidneys.

Grand mal = A major epileptic seizure.

Folliculitis = Inflammation of the hair follicles.

GDV = Gastric dilation volvulus; distension of the stomach with gas, which is unable to escape due to twisting.

Haemothorax = The presence of blood in the thoracic cavity.

Hemiplegia = Paralysis of one half of the body; the lesion is on the side of the brain opposite to the one paralysed.

Hepatic lipidosis = A serious condition of cats also known as fatty liver.

Hepatitis = Inflammation of the liver; usually due to viral infection or toxicity.

Hip dysplasia = A hereditary condition typically affecting large breeds of dog, especially the German Shepherd; the head of the femur does not fit correctly into the acetabulum.

Horner's syndrome = A condition in which there is a lesion on the path of sympathetic nerve fibres in the cervical region; symptoms include enophthalmos, ptosis and a contracted pupil.

Hydrocephalus = Enlargement of the skull caused by an accumulation of fluid around the brain or in the ventricles.

Hydrothorax = The presence of effused fluid in the pleural cavity.

Hyperadrenocorticism = A condition of over-secretion by the adrenal cortex. This may be due to a tumour of the adrenal cortex or pituitary gland. Also known as Cushing's disease or PDH (pituitary dependent hyperadrenocorticism).

Hyperaesthesia = Excessive sensitivity to touch and other sensations.

Hyperglycaemia = Excessive glucose in the blood.

Hyperkinesis = Excessive motor activity.

Hyperpnoea = Increased respiratory rate and depth.

Hyperthyroidism = Excessive activity of the thyroid gland. This condition is more common in cats than in dogs and is characterised by weight loss and tachycardia.

Hyphaema = Haemorrhage into the anterior chamber of the eye.

Hypoadrenocorticism = The underproduction of the hormones of the adrenal cortex; also known as Addison's disease.

Hypoglycaemia = An insufficiency of blood glucose.

Hypothyroidism = An insufficiency of thyroid secretion.

Icterus = Jaundice.

Idiopathic = Of unknown cause or origin.

IMHA = Immune mediated haemolytic anaemia.

Impetigo = A superficial, bacterial skin infection that is most often seen in puppies. It is characterised by multiple pustules and yellow scabs, particularly on the ventral abdomen; also known as juvenile pustular dermatitis or puppy pyoderma.

Interdigital dermatitis = See pododermatitis.

Iridocyclitis = Inflammation of the iris and ciliary body.

Labial dermatitis = Inflammation of the skin of the lips; usually seen in "jowly" dogs.

Juvenile pustular dermatitis = See impetigo.

Keratitis = Inflammation of the cornea.

Keratoconjunctivitis sicca = Inflammation of the cornea and conjunctiva due to insufficient tear production; also known as dry eye.

Ketoacidosis = A serious condition of diabetic animals that arises from the build up of ketones that accumulate in the blood.

Lacrimation = Tear production.

Marie's disease = Also known as chronic pulmonary arthroplasty. This disease of dogs is seen as a thickening of certain bones as a result of an intrathoracic or intrabdominal mass.

Meningitis = Inflammation of the meninges of the brain. The cause may be viral, bacterial, fungal or toxic.

Miotic drug = A drug that causes constriction of the pupil.

Moist dermatitis = See wet eczema.

Mucolytic = A drug that softens mucus, thus reducing the viscosity of bronchial secretions.

Myasthenia gravis = An extreme form of progressive muscle weakness.

Mydriatic drug = A drug that causes the pupil to dilate.

Nephritis = Inflammation of the kidney.

OCD = Osteochondritis dessicans; a disease of young dogs in which cartilage becomes excessively thickened.

Oliguria = A deficient secretion of urine.

Ophthalmoscope = An instrument used to illuminate and examine the interior of the eye.

Orthopnoea = Difficulty breathing whilst in recumbency.

Osteochondrosis = A developmental disease of articular cartilage in which the long bones are principally affected.

Osteodystrophy = Disease of bone during its development and growth.

Osteomalacia = A disease of bone that arises as a result of insufficient vitamin D; also known as Rickets.

Osteopathy = Any disease of bone.

Osteopenia = Abnormal rarefaction of bone that leads to the thinning of the skeleton and excessive bone resorption.

Osteoporosis = See osteopenia.

Otitis externa = Inflammation of the external ear canal.

Otitis interna = Inflammation of the inner ear.

Otitis media = Inflammation of the middle ear cavity.

Otodectes cyanotis = Ear mites.

Otoscope = See auroscope.

Ottorhoea = Any discharge from the ear.

Pancreatitis = Inflammation of the pancreas.

Panosteitis = Inflammation of all the structures of a bone.

Paracentesis = The puncture of the wall of a cavity with a needle, in order to draw off excess fluid or to obtain a sample for analysis.

Paralysis = Complete loss of function of an area of the body.

Paraparesis = Partial paralysis.

Paraplegia = Paralysis of the hind limbs.

Paresis = Muscle weakness with neurological deficits; the animal is still able to make coordinated walking movements providing that the body is supported.

Patent ductus arteriosus (PDA) = Failure of the ductus arteriosus to close as it should within a few days following birth.

Petit mal = A mild epileptic seizure.

Pinna = The earflap.

Pleurisy = Inflammation of the pleura.

Pneumonia = Inflammation of the lung with consolidation and exudation.

Pneumothorax = The presence of air within the pleural cavity.

Pododermatitis = Inflammation of the skin between the digits; also known as interdigital dermatitis.

Polyarthritis = The inflammation of several joints at the same time.

Polyuria = Increased frequency of urination.

Portosystemic shunt = Any vascular anastomosis between the hepatic portal vein and the systemic circulation.

Pruritis = Extreme irritation of the skin; a sensation within the skin that produces the desire to scratch in order to relieve the irritation.

Psychogenic neurodermatitis = A skin disease of cats associated with continual licking, cleaning or hair-pulling, attributed to stress factors or anxiety neurosis.

Psychogenic polydipsia = Excessive drinking due to stress related reasons rather than a physical cause.

Ptosis = Dropping of the upper eyelid due to paralysis of the 3rd cranial nerve.

Ptyalism = An abnormally large secretion of saliva.

Pulmonic stenosis = A congenital condition in which the cusps of the pulmonic heart valve are malformed. This may cause right-sided heart failure.

Pyelonephritis = Inflammation of the renal pelvis and cortex.

Pyoderma = Any purulent skin disease.

Pyothorax = Pus within the thoracic cavity.

Quadriplegia = Paralysis in which all 4 of the limbs are affected.

Rhinitis = Inflammation of the nasal mucous membranes.

Seborrhoea = an abnormally copious excretion of sebum that may make the skin appear oily.

Sertoli cell tumour = A neoplastic growth within the testis that may produce oestrogens that cause feminisation. Cryptorchid animals are most at risk.

Status epilepticus = A severe form of seizure in which the animal suffers a rapid succession of fits.

Syncope = A faint.

Tachypnoea = Increased respiratory rate.

Tenesmus = Painful or ineffectual attempts to urinate or defecate.

Tetraplegia = See quadriplegia.

Tonic phase = The period during a seizure in which the muscles tense up.

Tympanic membrane = The eardrum.

Urticaria = An acute or chronic allergic skin condition characterised by the recurrent appearance of an eruption of weals causing great irritation.

Uveitis = Inflammation of the uveal tract.

Von Willebrand's disease = An inherited bleeding disorder that arises as a result of clotting factor VIII. Dobermans are particularly susceptible.

Wet eczema = A nasty skin infection that comes up very quickly and is extremely red, sore and itchy; usually occurs as a result of an allergic reaction. Also known as acute moist dermatitis.

Wobbler syndrome = A neurological condition in which progressive ataxia and neck pain arise due to pressure on the cervical spinal cord from unstable discs, deformed vertebrae or hypertrophied spinal ligaments. This condition is also known as cervical spondylopathy.