tube

Concise Oxford English Dictionary © 2008 Oxford University Press:
tube/tjuːb/

▶noun

• 1 a long, hollow cylinder used for conveying or holding liquids or gases.

  ■ a long flexible metal or plastic container sealed at one end and with a cap at the other.

  ■ material forming tubes.

• 2 Anatomy, Zoology, & Botany a hollow cylindrical organ or structure in an animal or plant.

  ■ (tubes) informal a woman's Fallopian tubes.

• 3 (the Tube) Brit. trademark the underground railway system in London.

  ■ a train running on this system.

• 4 a sealed container, typically of glass and either evacuated or filled with gas, containing two electrodes between which an electric current can be made to flow.

  ■ a cathode ray tube, especially in a television set.

  ■ N. Amer. a thermionic valve.

• 5 (the tube) N. Amer. informal television.

• 6 (in surfing) the hollow curve under the crest of a breaking wave.

• 7 informal a cigarette.

• 8 Austral. informal a can of beer.

▶verb

• 1 (usu. as adj. tubed) provide with a tube or tubes.

• 2 convey in a tube.

– phrases
go down the tube (or tubes) informal be completely lost or wasted; fail utterly.

– derivatives
tubeless adjective.

– origin C17: from Fr. tube or L. tubus.