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1. pertaining to or resembling a hair.
2. in the circulatory system, one of the minute vessels connecting arterioles and venules, the walls of which act as a semipermeable membrane for interchange of various substances between the blood and tissue fluid. Capillary walls consist of thin endothelial cells through which body fluids and dissolved substances can pass. At the arterial end, the blood pressure within the capillary is higher than the pressure in the surrounding tissues, and the blood fluid and some dissolved substances pass outward through the capillary wall. At the venous end, the pressure within the tissues is higher and waste material and fluids from the tissues pass into the capillary, to be carried away for disposal.
arterial capillary a vessel lacking complete coats, intermediate between an arteriole and a capillary. Called also precapillary.
venous capillary a type of minute vessel that lacks a muscular coat and is intermediate between a venule and a capillary. Called also postcapillary.
a capillary opening into a venule.
ve·nous cap·il·lar·y(vē'nŭs kap'i-lar-ē)
A capillary opening into a venule.
One of the minute vessels that convey blood from a capillary network into the small veins (venules).
See also: capillary