Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «P»:
Piercing: Using a sharp
instrument, usually a
needle, to make a temporary or permanent hole through an
earlobe or other body part. Humans have practiced piercing
for body decoration since prehistoric times. Unless it is
performed using a sterile needle (preferably disposable),
piercing can ca...
Pigeon breast: Prominence of the breast bone (sternum).
Medically, pigeon breast is called pectus carinatum. ...
PIGF: Placental growth factor....
Pigment: A substance that gives color to tissue. Pigments are
responsible for the color of skin, eyes, and hair....
Pigmentation: The coloring of the skin, hair, mucous membranes, and retina of the eye.
Pigmentation is due to the deposition of melanin which is a coloring matter. The melanin is produced by specialized cells called melanocytes.
Other pigmented terms include hyperpigmentation (too much pigment), hyp...
Pigmented villonodular synovitis
Pigmented villonodular synovitis: A benign proliferative form of monoarthritis (arthritis in just one joint) that can occurs at any age but is most common in adults age 20-50. The joint most often affected is the knee with the hip, ankle, and shoulder affected less commonly. Pigmented villonodular ...
Piles: 1. A term in use since the 15th century for hemorrhoids.
2. A street name for crack cocaine....
Pill: In pharmacy, a medicinal substance in a small round or oval mass meant to be swallowed. Pills often contain a filler and a plastic substance such as lactose that permits the pill to be rolled by hand or machine into the desired form. The pill may then be coated with a varnishlike substance.
Pill splitter: A device for tablet splitting....
Pill splitting: See: Tablet splitting....
Pill, the: Commonly called "the pill,"
combined oral contraceptives are the most commonly used form of
reversible birth control
in the United States.
This form of birth control suppresses ovulation
(the monthly release of an egg from the ovaries) by the combined
actions of the hormon...
Piloerection: Erection of the
hair of the skin. Piloerection of the hair, for example, on the arm makes it "stand on end."
Piloerection starts when a stimulus such as cold or fright causes a discharge from the (involuntary) nervous system that triggers contraction of the little arrectores pilorum...
Pilonidal: Refers to an embedded (ingrown) hair or tuft of hair. Literally, a nest of hair. From the Latin pilus (meaning hair) and nidus (meaning nest)....
Pilonidal cyst: A special kind of abscess that occurs in the
cleft between the buttocks. Forms frequently in adolescence after long trips that involve sitting. The word "pilonidal" is derived from the Latin words pilus (meaning hair) and nidus (meaning nest)....
Pilonidal sinus: A sinus tract from which there may be chronic drainage of pus, due to an embedded tuft of hair, most often in the crease between the buttocks, but can occur elsewhere in the body, as between the fingers in barbers, hairdressers, and animal groomers. Surgical removal of the hair and...