tube

noun

• 1a long, hollow cylinder of metal, plastic, glass, etc., for holding or transporting something, chiefly liquids or gases.
• the inner tube of a bicycle tire.
• material made into cylindrical form; tubing:the firm manufactures steel tube for a wide variety of applications

• 2a thing in the form of or resembling a tube, in particular.
• a flexible metal or plastic container sealed at one end and having a screw cap at the other, for holding a semiliquid substance ready for use:a tube of toothpaste
• a rigid cylindrical container:a tube of lipstick
• [usually with modifier] Anatomy, Zoology, & Botany a hollow cylindrical organ or structure in an animal body or in a plant:Eustachian tube sieve tube
• (tubes) informal a woman’s fallopian tubes.
• a woman’s close-fitting garment, typically without darts or other tailoring and made from a single piece of knitted or elasticized fabric: [as modifier]:stretchy tube skirts
• (in surfing) the hollow curve under the crest of a breaking wave.

• 3 (the Tube) British trademark the subway system in London.
• a train running on the subway system in London:I caught the tube home

• 4a 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.
• (the tube) informal television:another wasted evening, sitting in front of the tube
• a vacuum tube.

verb

• 1 (usually as adjective tubed) provide with a tube or tubes: [in combination]:a giant eight-tubed hookah

• 2 informal fit (a person or animal) with a tube to assist breathing, especially after a laryngotomy.