Simple Definition of capillary

from our Learner's Dictionary

capillary

noun

ˈkæpəleri

British kəˈpɪləri

plural capillaries

: one of the many very small tubes that carry blood within the body : the smallest kind of blood vessel

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“Capillary.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/capillary. Accessed 22 Jun. 2026.

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