tube

American  

[toob, tyoob] / tub, tjub /

noun

tubes plural

1. a hollow, usually cylindrical body of metal, glass, rubber, or other material, used especially for conveying or containing liquids or gases.

2. a small, collapsible, cylinder of metal or plastic sealed at one end and having a capped opening at the other from which paint, toothpaste, or some other semifluid substance may be squeezed.

3. Anatomy, Zoology. any hollow, cylindrical vessel or organ.

   the bronchial tubes.

4. Botany.

   1. any hollow, elongated body or part.

   2. the united lower portion of a gamopetalous corolla or a gamosepalous calyx.

5. inner tube.

6. Electronics. electron tube.

7. Informal.

   1. television.

   2. a television set.

8. mailing tube.

9. the tubular tunnel in which an underground railroad runs.

10. the railroad itself.

11. Surfing Slang. the curled hollow formed on the underside of a cresting wave.

12. British. subway.

13. Australian Slang. a can of beer.

14. Older Slang. a telescope.

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verb (used with object)

tubed, tubing

1. to furnish with a tube or tubes.

2. to convey or enclose in a tube.

3. to form into the shape of a tube; make tubular.

idioms

1. down the tube / tubes, into a ruined, wasted, or abandoned state or condition.

tube British  

/ tjuːb /

noun

1. a long hollow and typically cylindrical object, used for the passage of fluids or as a container

2. a collapsible cylindrical container of soft metal or plastic closed with a cap, used to hold viscous liquids or pastes

3. anatomy

   1. short for Eustachian tube Fallopian tube

   2. any hollow cylindrical structure

4. botany

   1. the lower part of a gamopetalous corolla or gamosepalous calyx, below the lobes

   2. any other hollow structure in a plant

5. 1. US and Canadian equivalent: subway.  Also called: the underground.  an underground railway system

   2. the tunnels through which the railway runs

   3. the train itself

   4. (capital) the London underground railway system

6. electronics

   1. another name for valve

   2. See electron tube cathode-ray tube television tube

7. slang a television set

8. slang a stupid or despicable person

9. slang a bottle or can of beer

10. surfing the cylindrical passage formed when a wave breaks and the crest tips forward

11. an archaic word for telescope

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verb

1. to fit or supply with a tube or tubes

2. to carry or convey in a tube

3. to shape like a tube

tube More Idioms  

1. see down the tubes.

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Other Word Forms

Derived Forms

• multitube
  adjective
• tube-like
  adjective
• tubeless
  adjective
• tubelike
  adjective

Inflected Forms

Nouns

• tubes
  plural

Etymology

Origin of tube

First recorded in 1590–1600, tube is from the Latin word tubus pipe

Explanation

A tube is a pipe shape, a cylinder with a hollow space inside. If you're like most people, you sip your milkshake through a straw — a long, plastic tube. Chemists use glass tubes in labs, and plumbers work with pipes — tubes made of plastic and metal. Another kind of tube is the rubber one inside a tire. If you slide down a snowy hillside on an inflated tire tube, or ride through choppy water while sitting on one, you can also use tube as a verb. Though it's not true in the US, in London the subway is also familiarly known as the Tube.

Example Sentences

It was this dynamic that had Elizabeth Cotterell and Coen Ware deeply analyzing the film during a recent tube ride in London.

From The Wall Street Journal • Jun. 28, 2026

French-style villas stand to be bulldozed, along with modest Hanoi-style "tube" houses and densely packed low-rises.

From Barron's • Jun. 24, 2026

The device, which is about the size of a tube of lip balm and costs $90, is sold primarily through the pet supply website Chewy and connects to the owner’s smartphone through uCloudlink’s GlocalMe app.

From Slate • Jun. 20, 2026

They brandished the Mexican flag seemingly everywhere: on banners, painted on cheeks, emblazoned on Jaimes’ tube top.

From Los Angeles Times • Jun. 19, 2026

When he had lived upstairs, he had once tasted toothpaste when a careless guest left the cap off a tube.

From "Ralph S. Mouse" by Beverly Cleary

Related Words

• cylinder
• duct
• pipe
• pipeline
• tunnel