Definition of tube in English:

Share this entry


Pronunciation: /t(y)o͞ob/


1A long, hollow cylinder of metal, plastic, glass, etc., for holding or transporting something, chiefly liquids or gases.
Example sentences
  • A straw itself will not hold up well to this experiment, so see if you can get a tube of glass or plastic.
  • The idea is to use the plasma coating to line catheters - plastic tubes surgically inserted into the body so patients can rid themselves of waste products from the blood through a dialysis machine.
  • Catheters - small plastic tubes - are inserted into veins in the arm or leg to access the heart for procedures such as angioplasties and stent placements.
cylinder, pipe, piping, conduit, line, flue, hose, cannula, catheter, siphon, pipette, funnel, duct, pipeline, drain
1.1The inner tube of a bicycle tire.
Example sentences
  • He had also had many requests for new tyres and tubes and other bicycle parts.
  • The shape can be chubbier - more like a truck tire than a bicycle tube - which lowers the cost for a given plasma volume.
  • They specialize in refurbishing tubular tires with new tubes.
1.2Material made into cylindrical form; tubing: the firm manufactures steel tube for a wide variety of applications
More example sentences
  • By mid-1931, Stanley launched a line of garden tools manufactured with all steel tube handles and stampings.
  • The fuselage was built out of welded chrome-molybdenum steel tube with rod bracing and fabric covering.
  • Two wide wing bracing struts were built from steel tube and balsa wood and fabric covered.
2A thing in the form of or resembling a tube, in particular.
Example sentences
  • Three works could be manipulated; the massed tubes formed a square or circle mounted on a base that allowed a segment or the whole piece to be rotated by hand.
  • Like threads twisted together to form a rope, the possible flight paths formed tubes in space.
  • Usually, either spheres or tubes form, but not both.
2.1A 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
More example sentences
  • There is a new tube of toothpaste ready and waiting.
  • He remembers collecting toothpaste tubes, newspapers, pots and pans.
  • In their other hands were new toothbrushes, a tube of toothpaste and container of dental floss they received from their dentists.
2.2A rigid cylindrical container: a tube of lipstick
More example sentences
  • A home-made lunch is delivered in cylindrical tubes with four compartments each.
  • A shiny black purse, a tube of dark red lipstick, eyeshadow, white chub stick, eyeliner, and a weightless garment, fluttering to the ground.
  • As he walked away, Han took out a lipstick tube from her purse and began applying it to her lips.
2.3 [usually with modifier] Anatomy , Zoology , & Botany A hollow cylindrical organ or structure in an animal body or in a plant: Eustachian tube sieve tube
More example sentences
  • The bladder and rectum originate from a single hollow tube, the endodermal cloaca.
  • The trachea is unbranched, and is formed by the division of the foregut by a longitudinal septum into two tubes - the trachea and the esophagus.
  • The endothelial tube everywhere remains intact and continuous.
2.4 (tubes) informal A woman’s fallopian tubes.
Example sentences
  • For example, it is unclear how these superficial peritoneal lesions would give rise to infertility, especially if they were distant from the fimbria of the tubes or ovaries.
  • Mucus hostility means that the secretion from the neck of the womb is abnormal, and kills the sperm so that they cannot travel through the uterus to the tubes.
  • She will have an ultrasound scan of the womb, tubes and ovaries.
2.5A 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
More example sentences
  • For a more classic look, there's a square-necked jacket with lateral buttons worn with a tube skirt hemmed at just below the knees.
  • Or it can be a rip off because in the end it is just a piece of long stretch tube.
  • The lightweight tube dress goes straight from the beach to the bar.
2.6(In surfing) the hollow curve under the crest of a breaking wave.
Example sentences
  • At Shipsterns, I think he got the best wave, the biggest tube, although they said mine was bigger.
  • Formal elements include a foreground or apron of foaming wash, and beyond that a wall of wave as it forms a tube, then crests and crashes.
  • Just as with ocean waves, as the wave breaks it forms a tube.
3 (the Tube) British trademark The subway system in London.
Example sentences
  • Today's hot topic was the Tube lines of the London Underground.
  • First of all in London we have the Tube which is still owned by the Government, so comparisons can be made there.
  • So we have various views of the world map but drawn as a London Underground Tube map.
3.1A train running on the subway system in London: I caught the tube home
More example sentences
  • The use of tube trains has gone down by 40% at the weekends, and between 5 and 15% on week days.
  • However, on the train and tube, I heard lots of northern accents.
  • Instead I will be spending two hours a day on buses, trains and the tube.
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.
Example sentences
  • Early diodes in electronics were made from metal plates sealed inside evacuated glass tubes, which could be seen glowing in the innards of old radio sets.
  • Such lamps have two electrodes in a ceramic tube that contains small amounts of mercury and metal-halide salts.
  • Fluorescent lamps generate light by passing electricity through a tube filled with inert gas and a small amount of mercury.
4.1A cathode ray tube, especially in a television set.
Example sentences
  • Simply connect the inverter to an available molex connector, and then connect both cold cathode tubes to the inverter on the opposing side.
  • Look out for early signs of in-car computing, and the erosion of cathode-ray tubes by cheaper liquid-crystal displays.
  • Cathode ray tubes will shrink slightly over that period, from 171 million units to 145 million.
4.2 (the tube) North American informal Television: another wasted evening, sitting in front of the tube
More example sentences
  • A really bad skiing day is still better than a day spent running or sitting in front of the tube.
  • Sally spent countless hours in front of the tube last season watching the games she was unable to attend in person.
  • The online crowd cut back on television time, watching the tube 4.5 fewer hours per week than the no-Net group did.
4.3North American A vacuum tube.
Example sentences
  • The conduction of electricity in thin gases in vacuum tubes was the key to the discovery of the electron in 1897.
  • A vacuum tube (also called an electron tube or, in the UK, a valve) is a device sometimes used to amplify electronic signals.
  • This work contains the principles of operation of The Thermionic Vacuum Tube, and coordinates the phenomena encountered in a study of this field.


[with object]
1 (usually as adjective tubed) Provide with a tube or tubes: [in combination]: a giant eight-tubed hookah
More example sentences
  • They are believed to produce sound by moving air through tubed extensions of the larynx to nasal plugs located near the blowholes.
  • That said, the feedback I've heard from our testers indicate seating and inflating our tubeless road tires should be as easier, or even easier in some cases, than a tubed tire.
  • The precipitate was spread homogeneously over the entire surface of the tubed medium using a serologic pipette.
2 informal Fit (a person or animal) with a tube to assist breathing, especially after a laryngotomy.


go down the tubes (or tube)

informal Be completely lost or wasted; fail utterly: we watched his political career go down the tubes
More example sentences
  • Seeing my career go down the tubes always shakes me…
  • They know full well that unless they come up with a constant stream of big sellers their career will go down the tube.
  • Markets are collapsing and manufacturing is going down the tubes, but the people in the malls spend regardless.



Pronunciation: /ˈt(y)o͞obləs/
Example sentences
  • Two of the most important technological developments were Michelin's creation of the radial tyre in 1948, giving a vastly superior grip, and Dunlop coming up with the tubeless concept in 1972.
  • Esophageal manometry generally is used to accurately place ambulatory pH monitoring probes, although adequate placement recently has been reported with a tubeless system.
  • That said, the feedback I've heard from our testers indicate seating and inflating our tubeless road tires should be as easier, or even easier in some cases, than a tubed tire.


Pronunciation: /-ˌlīk/
Example sentences
  • Native bluebells are true blue in colour, the blooms are tube-like and elongated, with a delicate droop Spanish bluebells are more upright, the blooms are more of a shorter, open bell-shape.
  • The oesophagus (food pipe) is a tube-like structure, about 25 cm long, lying in the chest.
  • Tearing a piece from a large lump of kneaded dough on the metal table, the master baker swiftly rolled it out into a long, tube-like form.


Mid 17th century: from French tube or Latin tubus.

Words that rhyme with tube

boob, cube, droob, j'adoube, jube, lube, rube

For editors and proofreaders

Syllabification: tube

Share this entry

What do you find interesting about this word or phrase?

Comments that don't adhere to our Community Guidelines may be moderated or removed.