- The definition of a capillary is a small blood vessel that is part of the network of the small arteries and small veins, or an extremely thin tube through which nothing thicker than a human hair can pass.
A tiny blood vessel in your body that connects your smallest arteries (your arterioles) to your smallest veins (your venules) is an example of a capillary.
A close up of an eye showing the capillaries.
- of or like a hair, esp. in being very slender
- having a very small bore
- in or of capillaries
Origin of capillaryClassical Latin capillaris ; from capillus, hair
- Relating to or resembling a hair; fine and slender.
- Having a very small internal diameter: a capillary tube.
- Anatomy Of or relating to the capillaries.
- Physics Of or relating to capillarity.
- Anatomy One of the minute blood vessels that connect arterioles and venules. These blood vessels form an intricate network throughout the body for the interchange of various substances, such as oxygen and carbon dioxide, between blood and tissue cells.
- A tube with a very small internal diameter.
Origin of capillaryFrom Latin capillāris, from capillus, hair.
(comparative more capillary, superlative most capillary)
- of or pertaining to hair
- pertaining to a narrow tube
- A narrow tube
- (anatomy) Any of the small blood vessels that connect arteries to veins
From Latin capillāris (“pertaining to the hair”), from capillus (“the hair, prop. of the head”), from caput (“head”).