You are probably most familiar with the word capillary as a minute vessel that transports blood to larger vessels in the body, but a capillary can actually mean any tiny tubelike device that moves a liquid from point to point.

Capillary comes from the Latin word capillaris, meaning "of or resembling hair." The meaning stems from the tiny, hairlike diameter of a capillary. While capillary is usually used as a noun, the word also is used as an adjective, as in "capillary action," in which a liquid is moved along — even upward, against gravity — as the liquid is attracted to the internal surface of the capillaries.

Definitions of capillary
  1. noun
    any of the minute blood vessels connecting arterioles with venules
    synonyms: capillary vessel
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    a small intertwined group of capillaries in the malpighian body; it filters the blood during urine formation
    tomentum, tomentum cerebri
    a network of tiny blood vessels between the cerebral surface of the pia mater and the cerebral cortex
    type of:
    blood vessel
    a vessel in which blood circulates
  2. noun
    a tube of small internal diameter; holds liquid by capillary action
    synonyms: capillary tube, capillary tubing
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    type of:
    tube, tubing
    conduit consisting of a long hollow object (usually cylindrical) used to hold and conduct objects or liquids or gases
  3. adjective
    long and slender with a very small internal diameter
    “a capillary tube”
    synonyms: hairlike
    of relatively small extent from one surface to the opposite or in cross section
  4. adjective
    of or relating to hair
Word Family

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