Medical Term Glossary


Abdomen: portion of the body lying between the thorax and pelvis.

Abrasion: a scrape or scratch of the skin, mucous membranes, or cornea.

Abscess: cavity filled with pus.

Acute: of sudden onset; having a short course.

Adipose: fat; fatty.

Adrenal gland: paired glands, located near the kidneys, that produce various hormones

such as epinephrine and cortisol.

Aerobic: able to survive only in the presence of oxygen.

Alimentary: pertaining to food or nutrient, or to the digestive system.

Allergy: hypersensitivity aquired through exposure to a particular substance (allergen).

Alopecia: loss of hair.

Ambulate: to walk.

Anaerobic: able to survive only in the absence of oxygen.

Analgesic: agent that reduces or eliminates pain but does not cause loss of consciousness.

Anemia: condition characterized by lower-than-normal red blood cell count.

Anesthesia: state of being without sensation, especially pain. May or may not be

accompanied by unconsciousness (general anesthesia vs. local anesthesia).

Anesthetic: agent that produces anesthesia, thus abolishing pain.

Anestrus: period of sexual inactivity between two estrous periods.

Anomaly: marked deviation from normal.

Anorexia: lack of appetite.

Anterior: pertaining to the front of the body.

Antibiotic: drug used to kill bacteria and other microorganisms.

Antihistamine: agent that combats the effects of histamine.

Anti-inflammatory: agent that suppresses inflammation.

Antipruritic: agent that prevents itchiness.

Antipyretic: agent that reduces fever.

Antitussive: agent that combats coughing.

Anus: terminal opening or orifice of the alimentary canal (digestive tract).

Aorta: main trunk of the arterial system, originating from the left side of the heart.

Arrythmia: variation from normal heart rhythm.

Artery: vessels through which blood flows away from the heart to various parts of the body.

Arthritis: Inflammation of a joint; osteoarthritis.

Aspirate: to remove fluid or gas from a cavity by suction.

Asthma: a condition in which the bronchi (airways) narrow, causing wheezing and

respiratory difficulty.

Asymptomatic: showing no signs of disease.

Atrophy: wasting away of a part. Eg: muscle atrophy.

Auditory: pertaining to hearing.

Autoclave: machine that sterilizes medical instruments and materials by use of super-heated steam under pressure.

Autopsy: Examination of a body after death; see also necropsy.

Avian: pertaining to birds.


Bacteria: a one-celled microorganism that ma

y or may not cause disease.

Barium: a liquid that is radiopaque (cannot be penetrated by x-rays).

Benign: not malignant; with a favorable prognosis.

Bilateral: occurring on two sides.

Bile: fluid that aids in digestion; produced in the liver and stored in the gall bladder.

Biopsy: removal of a small amount of tissue from the body for examination, usually microscopic.

Bitch: a female dog.

Bladder: a sac serving as a receptacle for a secretion or excretion. Used alone, it refers to the urinary bladder.

Blood: fluid composed of water, cells, clotting factors and other chemicals, that circulates

through arteries and veins to supply nutrients and remove wastes from body tissues.

Bronchitis: inflammation of the bronchi.

Bronchus: a large air passage in the lungs. Pleural: bronchi.


Calculus: a stone or concretion formed inside the body; can also refer to dental tartar.

Cancer: a malignant tumor.

Canine: pertaining to dogs.

Canine tooth: large fang tooth in carnivores.

Capillary: tiny blood vessels.

Carcinoma: an invasive malignant tumor arising from epithelial tissues.

Cardiac: pertaining to the heart.

Cardiopathy: any disease of the heart.

Carnivore: animal that eats flesh or meat.

Cartilage: a specialized, fibrous connective tissue that provides a model in which most of the bones develop..

Castrate: surgical neutering of the male which involves the removal of both testicles.

Cataract: opacity of the lens of the eye.

Catheter: a tubular instrument used to withdraw fluid from the body (such as urine), or to administer fluids into the body (such as into a vein).

Centesis: tapping a body cavity or organ using a needle, aspirator or trochar.

Cholangiohepatitis: inflammtion of the gall bladder and liver.

Chronic: persisting over a long period of time.

Clot: a semi-solid mass, as of blood cells.

Coagulation: clot formation.

Colitis: inflammation of the colon.

Conjunctiva: membrane that lines the inner eyelids and covers the exposed surface of the eyeball.

Conjunctivitis: inflammation of the conjunctiva.

Contraindication: a circumstance that renders a particular treatment inappropriate or undesirable.

Convulsion: violent, involuntary contraction of muscles, often from a neurological disorder; seizure.

Cornea: the transparent anterior portion of the eye.

Cortisone: a major hormone produced by the adrenal glands.

Cranium: the skull.

Cryptorchid: a condition in which one or both testicles have not descended into the scrotum.

C-section: caesarian section; the surgical delivery of a term fetus.

Cyanosis: bluish discoloration of the mucous membranes and skin caused by poor tissue oxygenation.

Cytology: study of cells.


Debride: to surgically remove foreign matter and devitalized tissues from a wound.

Declaw: onychectomy; the surgical removal in cats of the nails and the nailbed.

Defecation: natural evacuation of fecal matter from the rectum.

Dehydration: excessive loss of water from the body.

Deramaxx: a commonly-used non-steroidal anti-inflammatory drug, prescribed to help alleviate pain or discomfort.

Dermatitis: inflammation of the skin.

Dermatosis: any disease of the skin.

Dewclaw: the "thumb" of dogs and cats.

Diarrhea: abnormal liquidity of the feces and/or increased frequency of defecation.

Disease: illness.

Distal: away from the center; out toward the end. The hand is distal to the arm.

Diuresis: increased production of urine.

Diuretic: an agent that increases urine production.

Dock: surgical removal of all or part of the tail.

Dorsal: pertaining to the back.

Dose: a specified amount of medication.

Drug: any substance used to prevent, diagnose, or treat disease.

Dysplasia: impaired growth process. See also Hip Dysplasia.


Edema: a swelling of tissue.

Electrocardiogram: tracing produced by electrical impulses associated with contractions

of the heart muscle; often called ECG or EKG.

Elizabethan collar: funnel-shaped piece of plastic placed around the animal's neck to prevent it from chewing on itself.

Emaciation: extreme weight loss.

Embolism: sudden obstruction of a blood vessel by a clot or foreign material.

Emesis: the act of vomiting.

Encephalitis: inflammation of the brain.

Endocarditis: inflammation of the lining of the heart chambers.

Endocrine: relating to ductless glands that secrete hormones into the blood stream.

Endotracheal tube: flexible tube placed into the trachea through the mouth to administer inhalent gases.

Enucleation: surgical removal of the eye.

Epidermis: the most outer layer of skin.

Epilepsy: a disease of the brain characterized by periodic seizures or loss of consciousness.

Esophagus: anatomical tube that connects the mouth to the stomach.

Estrus: the portion of the heat cycle during which the female is ready to breed.

Etogesic: a commonly-used non-steroidal anti-inflammatory drug, prescribed to help alleviate pain or discomfort.

Euthanasia: the painless inducement of death, usually by intravenous injection.

Excise: to cut out or off; to remove surgically.

Excretion: the act of discharging or removing products from the body, such as urine or perspiration.


Febrile: fever.

Feces: waste products discharged from the intestinal tract.

Feline: pertaining to cats.

Femur: bone extending from the pelvis to the knee; the thigh bone.

Fracture: the breaking of a bone.

Friable: easily torn or crumbled.

Fur ball: a hairball; trichobezoar.


Gallbladder: reservoir for bile located near the liver.

Gastritis: inflammation of the stomach.

Gastroenteritis: inflammation of the stomach and intestines.

Geriatrics: branch of medicine dealing with old or aging animals.

Gestation: period of pregnancy.

Gingiva: the gums.

Gingivitis: inflammation of the gums.

Grave: very serious or severe.


Hairball: clump of hair or fur, food, and other debris in the stomach.

Hematocrit: packed cell volume; volume percentage of red blood cells in whole blood.

Hematoma: localized collection of blood in an organ, space, or tissue.

Hemorrhage: escape of blood from a vessel; bleeding.

Hemostasis: arrest of bleeding.

Hepatitis: inflammation of the liver.

Hepatopathy: any disease of the liver.

Hernia: abnormal protrusion of an organ or tissue through a body wall.

Hip dysplasia: malformation of the hip joint; can lead to arthritis.

Histamine: naturally occuring substance found in all body tissues that is a component of the inflammatory reaction.

Histopathology: study of diseased tissues at the microscopic level.

Hives: raised, red patches of skin, often accompanied by itching; aka: urticaria.

Hormone: substance produced by an organ causing a specific effect on other organs or tissues.

Hypertension: high blood pressure.

Hyperthermia: high body temperature.

Hyperthyroidism: disease characterized by elevated thyroid hormone levels.

Hypotension: low blood pressure.

Hypothermia: low body temperature.

Hypothyroidism: disease characterized by decreased thyroid hormone levels.

Hysterectomy: excision of the uterus.


Icterus: yellow discolorations of body tissues caused by increased bile pigments; jaundice.

Idiopathic: of unknown cause.

Incise: to cut.

Incision: wound produced by sharp instrument.

Incisor: blade-like front tooth adapted for cutting.

Incontinent: unable to control urination or defecation.

Infection: invasion of the body by microorganisms.

Inflammation: localized tissue response to injury, characterized by heat, swelling, redness, pain and loss of function.

Injection: introduction of a fluid into a vessel or part.

Intestine: portion of the digestive tract; also called the bowel.

Intramuscular: within a muscle.

Intravenous: within a vein.

Intubate: to insert a tube into a body canal or hollow organ, such as the trachea or stomach.

Iris: colored membrane in the eye, surrounding the pupil.

Irrigate: to wash out or flush.


Jaundice: yellow discolorations of the skin and body tissues caused by increased bile pigments; common in severe liver disorders and some blood disorders; also called icterus.

Joint: junction between bones.


Keratitis: inflammation of the cornea.

Kidney: a paired organ that filters waste products from the blood to produce urine.


Laceration: a wound made by tearing or cutting.

Lacrimal: pertaining to tears.

Lance: to cut open with a pointed knife or scalpel.

Larynx: structure containing the vocal cords.

Lateral: pertaining to the side of the body.

Lesion: any discontinuity of tissue or loss of function.

Lethal: deadly or fatal.

Leukemia: malignant disease of the blood.

Leukocyte: a white blood cell.

Ligament: band of dense, fibrous tissue connecting bones and supporting joints.

Ligate: to tie off.

Ligature: material used to tie off a vessel.

Lingual: pertaining to the tongue.

Lipoma: benign tumor composed of fat cells.

Liver: large abdominal gland responsible for numerous critical metabolic functions.

Lumbar: part of the back between the chest and pelvis.

Lung: organ of respiration located in the chest cavity.

Luxation: dislocation, often to describe an injured joint.

Lymph: transparent, whitish liquid derived from tissue fluids.

Lymphatic: pertaining to a lymph vessel.


Malignant: tending to become progressively worse and result in death. Often refers to potentially fatal tumors.

Malocclusion: improper alignment of the teeth.

Mammary glands: glandular structures in the female that secrete milk.

Mandible: the lower jaw bone.

Mastectomy: excision of mammary tissue.

Medial: a position towards body midline.

Megacolon: an abnormally enlarged colon.

Melanoma: tumor comprised of cells containing melanin, a dark body pigment.

Meningitis: inflammation of the membranes enveloping the brain or spinal cord.

Metastasis: the spread of tumor cells from one area of the body to another.

Muzzle: the nose and upper and lower mouth; a device placed around the snout and jaw to prevent biting.


Narcotic: agent that produces stupor.

Necropsy: examination of a body after death. Necropsy is the preferred term for examination of animal cadavers, autopsy for humans.

Necrosis: death of tissue.

Necrotic: pertaining to dead tissues.

Neonatal: pertaining to the first few weeks after birth.

Neoplasm: cancer.

Nephrosis: any disease of the kidney.

Nerve: cord-like structure, composed of numerous fibers, that carries impulses between the central nervous system and other parts of the body.

Neurology: study of the brain, spinal cord, and nerves.

Neuter: to surgically remove the reproductive organs in either the male (castration) or female (spay).

NSAID: an acronym for non-steroidal anti-inflammatory drugs, often used for arthritis or post-operatively for surgical patients.

Nutraceuticals: A product that is considered a food additive or a food supplement. These products are not regulated by the Food and Drug Administration; therefore, efficacy cannot be guaranteed.


Occlusion: the act of closing off an obstruction.

Oncologist: cancer specialist.

Oncology: study of cancer.

Operation: surgical procedure.

Ophthalmic: pertaining to the eye.

Ophthalmology: study of disorders of the eye.

Orifice: the opening, entrance, or outlet of a body cavity.

Orthopedic: pertaining to bones and the skeletal system.

Ovariohysterectomy: surgical removal of the ovaries and uterus; spay.

Ovary: the sexual gland in the female in which ova (or eggs) are formed.

Oviduct: tubular passage that carries ova to the uterus.

Ovum, ova: the female reproductive cell, an egg.


Palate: partition separating the oral and nasal cavities.

Palpation: using the hands to feel body parts during physical examination.

Pancreas: gland that produces digestive enzymes, insulin, and glucagon.

Panleukopenia: viral disease of cats characterized by decreased numbers of white blood cells; feline distemper.

Papilloma: benign skin tumor; wart.

Paralysis: loss of the ability to move body parts.

Paranasal: around or near the nasal passages.

Paraplegia: paralysis of both rear legs.

Parasite: plant or animal that lives on or in another organism at the expense of the host.

Paresis: slight or incomplete paralysis.

Pelvis: the paired hip bones.

Perianal: located around the anus.

Periodontal: pertaining to the area around the tooth.

Pharynx: passage between the nostrils and the esophagus and larynx.

Pleura: membrane that lines the thoracic cavity.

Pleuritis: inflammtion of the pleura.

Pocket pet: refers to small mammalian pets, like gerbils, rats, hamsters, and guinea pigs.

Polydactyl: extra toes.

Posterior: pertaining to the rear or back part of the body.

Postoperative: after surgery.

Preoperative: before surgery.

Prescription: written direction for preparation and dosage of a drug.

Proestrus: period preceding estrus (heat).

Prolapse: protrusion of an organ, often through a normal body opening.

Prophylaxis: prevention of disease.

Prostate: an accessory sex gland in some male animals.

Prostatitis: inflammation of the prostate gland.

Proximal: near the center of the body, as opposed to peripheral or distal.

Pruritis: itchiness.

Pupil: the place in the center of the eye through which light is admitted.

Purulent: consisting of or containing pus.

Pyometra: life-threatening condition characterized by accumulation of pus in the uterus.


Quadruped: animal with four feet.

Queen: process of giving birth in cats; an adult intact female cat.


Radiograph: image on film produced by passage of x-rays through a body part.

Radius: a bone between the elbow and wrist.

Rectum: the distal portion of the large intestine, ending at the anus.

Respiration: the act of breathing.

Retina: the innermost layer of the eye.

Rhinitis: inflammation of the nasal passages.

Rimadyl: a commonly-used non-steroidal anti-inflammatory drug, prescribed to help alleviate pain or discomfort.


Sarcoma: malignant tumor.

Scapel: small surgical knife.

Scapula: shoulder blade.

Sclera: the white, outer part of the eyeball.

Sclerosis: hardening of tissues.

Sedative: agent that reduces activity or decreases excitement.

Seizure: convulsion.

Serum: the liquid portion of blood.

Sinus: cavity or hollow space.

Sinusitis: inflammation of paranasal sinus.

Spay: see ovariohysterectomy.

Sphincter: ring-like band of muscle that closes a natural body opening.

Spinal: pertaining to the vertebral column.

Spleen: a large organ near the stomach that stores red blood cells.

Sterile: free of microorganisms; unable to reproduce.

Steroid: compound in a group of chemicals that includes the sex hormones, glucocorticoids, mineralcorticoids, and bile acids.

Stethoscope: instrument used to listen to body sounds, like the heart beat.

Stifle: the knee.

Stitch: common term for a suture.

Subcutaneous: beneath the skin.

Superficial: near the surface.

Suture: material used to close a wound or tie off a bleeding vessel.

Systemic: affecting the body as a whole.


Tendon: a fibrous cord by which muscle is attached to bone.

Thoracic: pertaining to the thorax.

Thorax: the chest.

Thrombus: blood clot.

Thyroid: paired gland located in the neck that produces hormones regulating body metabolism.

Tibia: the shin bone.

Tick: an external parasite which feeds on the blood of its host.

Tissue: an aggregation of cells specialized in one function.

Topical: pertaining to a surface area; often refers to medicines used on the skin.

Torsion: twisting or rotation.

Toxemia: presence of bacterial toxins in the blood stream.

Toxicology: study of poisons.

Trachea: tubular airway connecting the larynx to the lungs; the windpipe.

Tranquilizer: drug used to calm an animal or relieve anxiety.

Transfusion: introduction of whole blood or blood components into the bloodstream.

Trauma: a wound or injury.

Tumor: a swelling or pathologic enlargement of tissues.

Tympanic membrane: the ear drum.


Ulcer: a local defect or excavation of the surface of a organ.

Umbilicus: the navel; belly button.

Unilateral: affecting only one side.

Ureter: tubular structure that conveys urine from each kidney to the urinary bladder.

Urethra: tube that conveys urine from the urinary bladder to the exterior of the body.

Urinalysis: laboratory analysis of urine.

Urination: passage or excretion of urine.

Urine: fluid formed in the kidneys, passed to the bladder for storage, and discharged through the urethra.

Urticaria: hives; an allergic condition of the skin characterized by large welts which itch.

Uterus: a hollow muscular organ found in female mammals, in which the fertilized ovum develops.


Vaccine: an agent, that when introduced into the body, stimulates an immune response against certain microorganisms.

Vagina: the canal in females extending from the vulva to the cervix.

Vein: vessel through which blood returns from organs and body parts to the heart.

Venipuncture: puncture of a vein with a needle; blood draw.

Ventral: pertaining to the belly or underside of a quadruped.

Ventricle: a chamber of the heart.

Vertebrate: any animal with a spinal column.

Veterinarian: doctor of veterinary medicine; really cool person.

Veterinary Technician: An animal nurse; also a really cool person.

Virus: a tiny infectious agent that replicates only inside a living cell, and lacks the ability for independent metabolism.

Viscera: any large organs located within the thoracic or abdominal cavities or pelvic canal.

Vomit: to cast up material from the stomach.

Vulva: external genitalia of females.


Wean: to discontinue nursing or suckling a young animal.

Whelp: the process of giving birth in dogs.

Wood's light: an ultraviolet light, often used to detect ringworm on the skin of animals.

Wound: any disruption of the continuity of a normal structure, as from an incision or injury.


X-rays: light rays of high amplitude which are passed by an electric generator through a glass vacuum tube (the x-ray tube). Such rays have special penetrative powers through body tissues.


Zoonosis: any disease of animals that can be transmitted to people under natural conditions.