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.(noun)
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.
See capillary in Webster's New World College Dictionary
Origin: L capillaris < capillus, hair
See capillary in American Heritage Dictionary 4
Origin: From Latin capillāris
Origin: , from capillus, hair.
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