Obligate carnivore (ob-li-geyt): An obligate carnivore, such as the cat, is one requiring nutrients found in sufficient quantities only in an animal-based diet

Obstipation (ob-stuh-pey-shuhn): A severe form of constipation that prevents the passing of stool or gas, usually caused by an obstruction in the intestinal tract

Obtunded (ob-tuhn-did): A diminished responsiveness to stimuli, often due to a state of reduced consciousness, which may occur in kittens with hypoglycemia

Occult (uh-kuhlt): Indicating a disease or condition that is clinically not apparent.

Off-label Use: Also known as extra-label, the use of a drug in a manner not approved by the Food and Drug Administration and not listed on the drug’s label, such as Methimazole for hyperthyroidism in cats

Oliguria (ol-i-gyoor-ee-uh): A medical condition in which there is not enough urination

Omphalitis (aam-fuh-lai-tuhs: An infection of the umbilicus and/or surrounding tissues that occurs primarily during the neonatal period and can rapidly progress to sepsis and death

Onychectomy (uh-nee-kek-tuh-me): An elective surgical procedure, also known as declawing, that involves the removal of the third phalanx bone using a guillotine-type nail clipper, surgical blade or laser

Oocyst (oh-uh-sist): The stage in the life of certain parasites in which they are encapsulated and usually passed through droppings

Opisthotonus (ow-pis-thuh-tow-nuhs): The abnormal, extreme extension of the head and neck toward the back caused by muscle spasms, which may occur with seizures

Otitis (oh-tahy-tis): Inflammation of the ear canal

Otoscope (oh-tuh-skohp): A hand-held instrument for examining the external canal and tympanic membrane (eardrum) of the ear

Ovariohysterectomy (oh-vuh-ree-o his-tuh-rek-tuh-mee): The surgical removal of the ovaries and uterus; generally referred to as spay when referring to female companion animals


Palpation (pal-pey-shuhn): Examination by finger pressure to detect growths, changes in underlying organs, and unusual tissue reactions to pressure.

Pancreatitis (pan-kree-uh-tahy-tis): Inflammation of the pancreas

Pandora syndrome: A disorder resulting from chronic anxiety (stressors that the cat finds threatening), which may lead to urinary problems, such as feline interstitial cystitis,  in cats

Parenteral (pa-ren-ter-uhl): Feeding intravenously (via a vein), which may be needed because of uncontrolled vomiting

Parturition (pahr-too-rish-uhn): The act of giving birth

Pediculosis (puh-dik-yuh-loh-sis): The condition of being infested with lice

Periuria  (per-ee-yoo-rahy-uh): Urination outside the litter box, which may be caused by medical  (infection, arthritis) or behavioral (location of litter box, aversion to litter) factors

Pheromone (fer-uh-mohn): A chemical released by an animal that influences the physiology or behavior of other members of the same species

Pica (pahy-kuh): Eating non-edible materials such as wool, plastic and cellophane, which can cause intestinal obstruction and require surgery

Piloerection (pai-low-uh-rek-shun): The lifting of the fur, typically on the back and tail, caused by the contraction of tiny muscles at the base of each hair, which may occur when a cat is frightened

Plasma drops (plaz-muh): A treatment option for deep or severe corneal ulcers, which requires using a cat’s plasma, the liquid part of the blood, to speed up healing

Plasma Cell Pododermatitis (poh-doh-dur-muh-tahy-tis): Inflammation caused by the infiltration of plasma cells into the paw pad, typically the central one, of more than one foot, which may heal spontaneously or require lifelong treatment

Polycythemia (paa-luh-see-mee-uh): A rare disease in cats characterized by the overproduction of red blood cells by the bone marrow

Polydactyl (pol-ee-dak-til): The presence of extra toes due to abnormal activity by the sonic hedgehog protein during early development; see Janus

Polydipsia (pol-ee-dip-see-uh): Excessive thirst

Polyestrous (pol-ee-es-truhs): Having several estrus cycles during a breeding season and continuing to come into heat if not bred

Polyphagia (pol-ee-fey-jee-uh): Excessive appetite or overeating

Polyuria (pol-ee-yoor-ee-uh): Urinating larger volumes than normal

Primordial pouch (prahy-mawr-dee-uhl powch): The extra loose skin and some fatty tissue along the belly that protects the vital organs, provides flexibility and expands for food storage; all cats are born with a primordial pouch

Prognosis (prog-noh-sis): The forecast of the probable survival or recovery following a disease or injury

Pruitis (proo-rahy-tuhs): Any intense sensation of itching, which may occur with fleas, infection and allergies

Purulent (pyoor-uh-luhnt): Being full of, containing, forming, or discharging pus

Pus (puhs): A thick, yellowish-white fluid seen in wounds and sores and containing white blood cells, microorganisms, and tissue debris

Pyelonephritis (pahy-uh-loh-nuh-frahy-tis): Inflammation of the kidney and its pelvis, caused by a bacterial infection

Pyoderma (pai-uh-dur-muh: Any skin eruption characterized by pustules or the formation of pus

Pyometra (pai-ow-meh-truh): A disorder characterized by the accumulation of a large amount of pus in the uterus

Pyrexia (pahy-rek-see-uh): A feverish condition