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(prō″tō-zō-ŏl′ō-jē) [Gr. protos, first, + zoon, animal, + logos, word, reason] The branch of science dealing with the study of protozoa.


(prōt-ă-zō′ŏn″) pl. protozoa Unicellular organism. SEE: Protozoa.


(prō-trakt′) [L. protrahere, to draw out, prolong] To extend or lengthen in time or space. 2. In anatomy, to extend or protrude forward and outward.


(prō-trăk′shŭn) [″ + L. protractus, dragged out] The extension forward or drawing forward of a part of the body such as the mandible.


(prō-trăk′tor) [L. protractus, dragged out] 1. An instrument formerly used to remove foreign bodies from wounds. 2. A muscle that draws a part forward; the opposite of retractor. 3. A semicircular device for drawing angles.


[L. protrudere] To project; to extend beyond a border or limit.


(prō-troo′zhŭn) The state or condition of being thrust forward or projecting. In dentistry, particularly related to the position of the mandible, as opposed to retrusion.


(prō-tu′bĕr-ăns) [Gr. pro, before, + L. tuber, bulge] A part that is prominent beyond a surface, like a knob.

external occipital p. A bony bump or elevation in the midline of the lower part of the back of the skull in the middle of the occipital bone. It is more prominent in males than in females.


(prov″ĭ-den′sē-ă) A genus of gram-negative urease-producing bacillary bacteria. Species that infect human beings include P. stuartii and P. rettgerii.


(prŏ-vīd′ĕr) A professional who gives health care services, or an institution that supervises the rendering of such services.

application service p. A company that offers individuals or enterprises access over the Internet to applications and services that would otherwise have to be located on their own computers.

limited-service p. Health care providers or institutions, such as outpatient surgery centers or facilities, that provide care to a market niche, i.e., to those people with a limited number of diseases or conditions.

mid-level p. A category of healthcare professionals that includes physician assistants, nurse midwives, nurse anesthetists, and nurse practitioners. SYN: mid-level practitioner.

nonphysician health care p. Nonphysician p.

nonphysician p. A health care professional licensed to provide healing services that complement or supplement those provided by a physician. Such providers include midwives, nurse practitioners, optometrists, physican assistants, physical or occupational therapists, psychologists, social workers, and chiropractors. In many settings, physicians and nonphysician ...

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