Category: P

  • Pinta

    A skin disease of the tropical regions of America, in which the skin on the hands and feet swells and loses colour, caused by a spirochaete Treponema. Skin infection caused by the Treponema cara-teum spirochete and common in Central and South America; it is characterized by a slowly enlarging papule, followed by a generalized rash,…

  • Pins and needles

    An unpleasant tingling sensation, usually occurring after a temporarily restricted blood supply returns to an arm or leg (informal). A form of paraesthesia, or disturbed sensation, such as may occur, for example, in neuritis or polyneuritis. A sensation of tingling or pricking in a particular area of the skin, often accompanied by numbness and occasionally…

  • Pinnaplasty

    A cosmetic surgical procedure to correct the shape of the ear.  

  • Pinguecula

    A condition affecting elderly people, in which the conjunctiva in the eyes has small yellow growths near the edge of the cornea, usually on the nasal side. Slightly elevated, irregular, yellow elastic-tissue deposit in the conjunctiva (mucous membrane lining of the eye) that may extend to, but does not cover, the cornea. A soft, yellowish,…

  • Pineal body

    A small cone-shaped gland situated below the corpus callosum in the brain, which produces melatonin and is believed to be associated with the circadian rhythm. A pea-sized mass of tissue attached by a stalk to the posterior wall of the third ventricle of the brain, deep between the cerebral hemispheres at the back of the…

  • Pinch

    An act of squeezing the thumb and first finger together. A quantity of something which can be held between the thumb and first finger. A type of hand prehension. The pinch of the human hand is achieved principally through holding objects between the thumb and index finger or the index and long fingers.  

  • Pin

    A small sharp piece of metal for attaching things together. A metal nail used to attach broken bones. In orthopedics, rodlike metal device used to secure fragments of a bone. A short, slim piece of wire, plastic, or metal. It may have one end blunt and the other sharp.    

  • Pimply

    Covered with pimples.  

  • Pilus

    One hair. Hair-like process on the surface of a bacterium.  

  • Pilot study

    A small version of a project which is carried out first, in order to discover how well it works and to solve any problems, before going ahead with the full version.