top of page

Medical Dictionary

Medical Dictionary

Medical Terminology Explained.


Abscess                A pocket of infected pus

Anterior                Refers to the front of the body

Acute                    Signs that happen quickly and become worse quickly

Atopy                    An inherited predisposition towards the development of an allergy

Atrophy                 Wasting or shrinking of a tissue or an organ

Antibiotic              Given to treat bacterial infections e.g. penicillin, tetracycline and gentamicin

Antibody               Produced by cells of the immune system in response to bacteria, virus, toxins etc

Ascites                  Fluid build-up in the abdominal cavity

Ataxia                    Incoordination

Antibacterial         Used to prevent the growth and/or spread of bacteria

Ambulatory           Able to move and walk



Blepharospasm     Spasm of the eyelid muscles, causing squinting

Bilateral                 Something happening on both sides

Benign                   A tumour that is not malignant and therefore usually less serious

Blood smear          A thin layer of blood smeared on a slide and examined under a microscope to study

                              the blood cells

Bacterium              Single-celled organisms that exist in their millions, some of which can be harmful

Biopsy                   Procedure performed by a vet where a small sample of tissue is taken from the

body for further testing


Chronic                    Long-term issue

Contagious              A disease which can be passed from one person or animal to another by direct


Corticosteroid          An anti-inflammatory drug given to reduce pain and support healing


Dermatitis                Inflammatory skin disease

Dermatophytosis       Fungal skin disease e.g. Ringworm

Distended                  When something is swollen from pressure from the inside, such as bloat


Endoparasite              Parasites that live inside the host, usually in the gut, lungs, heart and blood


Ectoparasite               Parasites that live in the skin or on the skin surface of the host, such as lice,

mites and ticks

Electrolytes                ‘Salts’ needed to maintain the vital body fluids, nerve impulses and for the

healthy function of muscles and circulatory system

Endoscope               Used to examine the internal organs or cavities


Guttural Pouch             Positioned beneath the ear on each side of the head, sacs of air that extend

from the Eustachian tube


Hypothermia              Dangerously low body temperature, caused by the body losing heat faster than

it can produce it


Intramuscular injection When a medication is injected into the depth of specifically selected


Infection                     A condition when bacteria or viruses that cause disease have entered into the


Idiopathic             When the cause of a disease is unknown

Inflammation            Caused by the body’s immune system in response to an irritant. Causes

swelling, pain, redness and heat

Intravenous injection     When something is injected into a vein


Lumpectomy                 Surgical procedure to remove a lump


MRI                              Magnetic Resonance Imaging. Used to visualise bone, soft tissue and

inflammation or fluid build up

Mange                        Found in the mane and tail area and caused by microscopic mites that cause

irritation of the skin

Melanoma                 Skin tumour mainly found in grey horses, usually on the head, neck and

underside of the tail

Malignant                   A tumour that can spread to other parts of the body, has irregular borders and

grows fast. Usually more serious than a benign tumour.


Nasogastric tube          Used for nasogastric intubation. The hollow tube is passed up the horse’s

nose, down the oesophagus and into the stomach


Ocular                      Anything to do with the eyes

Ophthalmoscope Device used to look into the eye

Otoscope                 Medical device used to look into the ears


Parasitism                 Describes the close relationship between the host and the parasite. The

parasite causes harm to the host

Posterior                       Refers to the direction of the back of the body

Peritonitis                Inflammation of the peritoneum, which is the membrane that lines the

abdominal cavity

Polyp                            A growth of tissue from a surface in the body

Prognosis                   The likely outcome of a disease or condition

Prolapse                     Displacement of an organ, or part of it, from its normal place. Usually

downwards or outwards, and often protruding from an orifice

Pyoderma                 Skin disease in which pus is formed


Rhinitis                         Inflammation of the nasal passages


Sinusitis                        Inflammation of a sinus

Skin scrape                   Performed by a vet, a scalpel blade is used to collect samples from fresh skin

lesions to identify ectoparasites or other pathogens

Superficial                  When something is closer to the surface of the body

Sporadic                    When something occurs at irregular intervals

Subcutaneous injection  When an injection is administered below the skin


Topical                   Medication to be used on the surface of the body

Tachycardia            Heart beating faster than normal

Tendinitis               Inflammation of the tendons

Tumour                 An abnormal mass of tissue. Can be benign or malignant


Unilateral              Affects only one side of the body

Ultrasonography   A procedure using sound waves to look at tissues and organs inside the body

Urinalysis           Diagnostic test to look at the urine


Viral                Disease caused by a virus, a much smaller pathogen than a bacteria

Viscera             Refers to the organs of the body

bottom of page