capillary

1 of 2

adjective

cap·​il·​lary ˈka-pə-ˌler-ē How to pronounce capillary (audio)
-ˌle-rē,
 British usually  kə-ˈpi-lə-rē
1
a
: resembling a hair especially in slender elongated form
capillary leaves
b
: having a very small bore
a capillary tube
2
: involving, held by, or resulting from surface tension
capillary water in the soil
3
: of or relating to capillaries or capillarity

capillary

2 of 2

noun

plural capillaries
1
: a minute thin-walled vessel of the body
especially : any of the smallest blood vessels connecting arterioles with venules and forming networks throughout the body
2
: a tube (as of glass) having a very small bore

Examples of capillary in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Adjective
The formula includes rose, green tea, licorice, and chamomile—ingredients that support capillary health and promote skin repair, resulting in a more balanced complexion. Maya Gandara, StyleCaster, 18 Mar. 2025 The ebb and flow of blood through capillary vessels changes the amount of light reflected from the skin. The Physics Arxiv Blog, Discover Magazine, 13 Mar. 2025
Noun
Aging can also cause a decrease in the body’s fatty protective layer, leaving small blood vessels, known as capillaries, more vulnerable to breaking. Meredith Kile, People.com, 26 Feb. 2025 The temperature control center in your hypothalamus has ordered the web of surface capillaries in your skin to constrict. Outside Online, 19 Feb. 2025 See All Example Sentences for capillary

Word History

Etymology

Adjective

French or Latin; French capillaire, from Latin capillaris, from capillus hair

First Known Use

Adjective

14th century, in the meaning defined at sense 1a

Noun

1667, in the meaning defined at sense 1

Time Traveler
The first known use of capillary was in the 14th century

Browse Nearby Words

Cite this Entry

“Capillary.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/capillary. Accessed 1 Apr. 2025.

Kids Definition

capillary

1 of 2 adjective
cap·​il·​lary ˈkap-ə-ˌler-ē How to pronounce capillary (audio)
1
: having a long slender form and a very small inner diameter
a capillary tube
2
: of or relating to capillaries or capillarity

capillary

2 of 2 noun
plural capillaries
: a capillary tube
especially : any of the tiny blood vessels connecting the small arteries and veins

Medical Definition

capillary

1 of 2 adjective
cap·​il·​lary
ˈkap-ə-ˌler-ē, British usually kə-ˈpil-ə-rē
1
a
: resembling a hair especially in slender elongated form
b
: having a very small bore
a capillary tube
2
: involving, held by, or resulting from surface tension
3
: of or relating to capillaries or capillarity

capillary

2 of 2 noun
plural capillaries
1
: a minute thin-walled vessel of the body
especially : any of the smallest blood vessels connecting arterioles with venules and forming networks throughout the body
2
: a capillary tube

More from Merriam-Webster on capillary

Last Updated: - Updated example sentences
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