capillary

1 of 2

adjective

cap·​il·​lary ˈka-pə-ˌler-ē 

-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

Adjective

These can cause increased pressure on your blood vessels, which can lead to capillary rupture. —Brandi Jones, Msn-Ed, Health, 7 Feb. 2025

The narrow grooves between these rows naturally draw in liquid water via capillary action. —Ben Coxworth, New Atlas, 2 Feb. 2025

Noun

These sports develop when capillaries, small blood vessels, break and leak blood into your skin. —Brandi Jones, Msn-Ed, Health, 7 Feb. 2025

One of the molecules that causes those capillaries to open up is called nitric oxide; the discovery of its role in circulation was rewarded with a Nobel Prize, in 1998, and led to, among other things, the development of Viagra. —Nicola Twilley, The New Yorker, 3 Feb. 2025

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

Phrases Containing capillary

• capillary attraction
• capillary electrophoresis

Kids Definition

capillary

1 of 2 adjective

cap·​il·​lary ˈkap-ə-ˌler-ē 

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