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

My go-to for watering is using a capillary mat under the seed tray. —Betty Cahill, The Denver Post, 10 Feb. 2025

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