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

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Etymology

Origin of tube

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

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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

See Examples For:

tube tubes tubed tubing

Each tube measured approximately 300 nanometers across and 150 nanometers tall.

From Science Daily ● Oct. 28, 2026

Removing the nodule can take place under general anaesthetic with the patient breathing through a tube.

From Barron's ● Oct. 13, 2026

Early reports suggested that she fell ill after breaking a test tube.

From Slate ● Oct. 8, 2026

Then she woke up in a hospital with a tube down her throat and people she didn't know.

From BBC ● Oct. 7, 2026

“I did. But then, when everything was bubbling in the test tube, I had a brainstorm. I added a secret ingredient.”

From "The Smartest Kid in the Universe" by Chris Grabenstein

An on-floor engineer remarked that they sell their scrap metal, and the price has skyrocketed—something they take as a sure indication that the economy is going down the tubes.

From Slate ● Oct. 29, 2026

Inside: dozens of small boxes with barcoded glass tubes, collectively containing one hundred billion genes.

From BBC ● Oct. 28, 2026

This shuttle stack sits in flight configuration, almost exactly as it would look on the cusp of liftoff, besides the yellow torque tubes lining the orbiter’s white shell like external ribs.

From Los Angeles Times ● Oct. 28, 2026

Every two weeks, researchers collected air samples through thin tubes installed beneath the ground and analyzed them in a laboratory.

From Science Daily ● Oct. 17, 2026

The boys had spent every spare moment practicing with the cardboard tubes that their aunt Gertrude had given them.

From "Hopping Mad (The Hardy Boys: Secret Files, #4)" by Franklin W. Dixon

This device comes in two forms, tubed and tubeless.

From BBC ● Dec. 14, 2024

The Faroe Islands is a self-governing archipelago within the Kingdom of Denmark, where there is also a strong affinity for meat served in tubed form.

From Salon ● Nov. 18, 2024

The opening of the tubed slide was small, and I thought I should lie down to avoid whacking my head.

From New York Times ● Aug. 24, 2017

He was a tall Dane, holding a tubed black device that he called a smoking gun.

From The New Yorker ● Apr. 4, 2016

Even during her year in London she had joined other girls in weekend bicycling excursions out of town, or tubed to Golder's Green or Shepherd's Bush in search of country walks.

From The Nest Builder by Beatrice Forbes-Robertson Hale

As a child, Franzoy often went tubing on the river or splashed with playmates in gurgling irrigation canals.

From The Wall Street Journal ● Oct. 21, 2026

They’re doing it from this little antechamber through 7 feet of tubing.

From Slate ● Oct. 6, 2026

In one video, the workers unwind a line of black tubing, or conduit, from a spool the size of a small car, before feeding it into the ground.

From MarketWatch ● Sep. 19, 2026

Certain lots were found to have internal tubing tears, which risk under-delivering insulin to patients.

From Barron's ● Apr. 30, 2026

At home, sugaring time would come soon, and already we’d carried the pails and the taps and the tubing down from the barn loft and begun to wash them all out.

From "Orbiting Jupiter" by Gary D. Schmidt

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