tube

noun

ˈtüb 

ˈtyüb

1

: any of various usually cylindrical structures or devices: such as

a

: a hollow elongated cylinder

especially : one to convey fluids

b

: a soft tubular container whose contents (such as toothpaste) can be removed by squeezing

c(1)

: tunnel

(2)

British : subway sense b

d

: the basically cylindrical section between the mouthpiece and bell that is the fundamental part of a wind instrument

2

a

: a slender channel (such as a fallopian tube or a pollen tube) within a plant or animal body : duct

b

: the narrow basal portion of a corolla with united petals or a calyx with united sepals

3

: inner tube

4

a

: electron tube

especially : vacuum tube

b

: cathode-ray tube

especially : a television picture tube

c

: television

5

: an article of clothing shaped like a tube

a tube top

tube socks

tubed

ˈtübd 

ˈtyübd

adjective

tubelike

ˈtüb-ˌlīk 

ˈtyüb-

adjective

see also:

down the tube

Synonyms of tube

• pipe
• conduit
• channel
• funnel

Examples of tube in a Sentence

She was breathing oxygen through a tube.

watched the liquid move through the tube between the flasks and recorded the movement in his chemistry notebook

Recent Examples on the Web

In the middle of the BioCharger, within the geometric, connected plates of glass, is a Tesla coil, which ionizes the surrounding 12 glass tubes that hold six noble gases, the gases in the earth’s atmosphere. — Rebecca Leib, Los Angeles Times, 2 Sep. 2026

The design introduced major changes to the forward section of the submarine, including a Large Aperture Bow sonar array and two Virginia Payload Tubes replacing the 12 individual vertical-launch tubes used on earlier boats. — Kaif Shaikh, Interesting Engineering, 1 Sep. 2026

Do not swim, wade, tube, kayak or participate in other activities involving contact with river water. — Zach Hillstrom, USA Today, 31 Aug. 2026

Star was placed on a tiny stretcher, with tubes hooked up to her wrist and nose. — Ruby Cramer, New Yorker, 31 Aug. 2026

Word History

Etymology

French, from Latin tubus; akin to Latin tuba trumpet

First Known Use

1651, in the meaning defined at sense 1

Phrases Containing tube

• auditory tube
• breathing tube
• bronchial tube
• cathode-ray tube
• discharge tube
• down the tube
• electron tube
• endotracheal tube
• Eustachian tube
• Fallopian tube
• feeding tube
• flash tube
• image tube
• inner tube
• neural tube
• photomultiplier tube
• picture tube
• Pitot-static tube
• Pitot tube
• pollen tube
• shock tube
• sieve tube
• snow tube
• speaking tube
• static tube
• test tube
• test-tube baby
• the tube
• thistle tube
• torpedo tube
• tube foot
• tube nucleus
• tube pan
• tube sock
• tube top
• tube worm
• vacuum tube
• X-ray tube

Rhymes for tube

• boob
• cube
• lube
• rube
• hypercube
• nanotube
• phototube

Kids Definition

tube

noun

ˈt(y)üb 

1

a

: a slender channel within a plant or animal body : duct

b

: a long hollow cylinder

especially : one to carry fluids

c

: the part of a wind instrument that connects the mouthpiece with the open end

2

: a soft container shaped something like a tube whose contents (as toothpaste or glue) can be removed by squeezing

3

: inner tube

4

: electron tube

5

: television sense 2

6

: an article of clothing shaped like a tube

tube socks

tubed

ˈt(y)übd 

adjective

tubelike

ˈt(y)ü-ˌblīk 

adjective

Medical Definition

tube

1 of 2 noun

ˈt(y)üb 

1

: a slender channel within a plant or animal body : duct see bronchial tube, eustachian tube, fallopian tube

2

a

: an often complex piece of laboratory or technical apparatus usually of glass and commonly serving to isolate or convey a product of reaction

a distillation tube

b

: test tube

3

: a soft tubular container whose contents (as toothpaste) can be dispensed by squeezing

4

: a hollow cylindrical device (as a cannula) used for insertion into bodily passages or hollow organs for removal or injection of materials

tube

2 of 2 transitive verb

tubed; tubing

: to furnish with, enclose in, or pass through a tube

the patient is then anesthetized … and tubed

—Anesthesia Digest