tube

American  

[toob, tyoob] / tub, tyub /

noun

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

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

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

Philo Farnsworth in the U.S. used the cathode-ray tube in his system, which became the standard.

From The Wall Street Journal • Apr. 26, 2026

His miniature fingernail polish paintings of everyday objects — a purse, a lipstick tube, a stiletto — are equal parts playful and macabre.

From Los Angeles Times • Apr. 21, 2026

Maybe the tube just irritated something, I thought.

From Slate • Apr. 18, 2026

She has had major surgery - her womb and part of her bowel have been removed, and she now has to drain her own bladder using a small tube.

From BBC • Apr. 14, 2026

I run from a green flare shooting out of Taylor’s tube.

From "Wayward Creatures" by Dayna Lorentz

Related Words

• cylinder
• duct
• pipe
• pipeline
• tunnel