from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A hollow cylinder, especially one that conveys a fluid or functions as a passage.
  • noun An organic structure having the shape or function of a tube; a duct.
  • noun A small flexible cylindrical container sealed at one end and having a screw cap at the other, for pigments, toothpaste, or other pastelike substances.
  • noun Music The cylindrical part of a wind instrument.
  • noun An electron tube.
  • noun A vacuum tube.
  • noun Botany The lower, cylindrical part of a gamopetalous corolla or a gamosepalous calyx.
  • noun A tunnel.
  • noun An underground railroad system, especially the one in London, England.
  • noun The elongated space inside a wave when it is breaking.
  • noun An inner tube.
  • noun An inflatable tube or cushion made of rubber or plastic and used for recreational riding, as behind a motor boat or down a snow-covered slope.
  • noun Television.
  • noun A television set.
  • noun Informal The fallopian tubes.
  • intransitive verb To provide with a tube; insert a tube in.
  • intransitive verb To place in or enclose in a tube.
  • intransitive verb To ride or float on an inflated tube for recreation.
  • idiom (tubes/tube) Into a state of failure or ruin.

from The Century Dictionary.

  • To furnish with a tube or tubes.
  • To receive or inclose in a tube.
  • noun A city subway in the form of a tunnel.
  • A pipe or hollow cylinder, especially when of small size and used as a conduit for liquids, or for containing liquids, as in some forms of scientific apparatus.
  • Specifically, the main body of a musical instrument of either the wood wind or the brass wind group. The bore of such instruments is usually conical, but sometimes cylindrical.
  • In anatomy and zoology, a hollow tubular organ; a pipe, canal, or duct conveying fluid or gas; especially, a pipe which seems to be empty—that is, conveys air: as, the bronchial tubes; the Eustachian tube.
  • In botany, any hollow elongated body or part of an organ: applied especially to a gamopet-alous corolla or gamosepalous calyx, also to a united circle of stamens (see cut 9 under stamen).
  • A priming-tube.
  • A telescope, or that part of it into which the lenses are fitted.
  • The barrel of a chain-pump.
  • A small receptacle of drawn lead, of approximately tubular form, closed at the bottom by bending it over twice or three times on itself, and having a screw-cap at the top, used to hold pigments or similar matter in a semifluid condition.

from the GNU version of the Collaborative International Dictionary of English.

  • transitive verb To furnish with a tube.
  • noun A hollow cylinder, of any material, used for the conveyance of fluids, and for various other purposes; a pipe.
  • noun A telescope.
  • noun A vessel in animal bodies or plants, which conveys a fluid or other substance.
  • noun (Bot.) The narrow, hollow part of a gamopetalous corolla.
  • noun (Gun.) A priming tube, or friction primer. See under Priming, and Friction.
  • noun (Steam Boilers) A small pipe forming part of the boiler, containing water and surrounded by flame or hot gases, or else surrounded by water and forming a flue for the gases to pass through.
  • noun A more or less cylindrical, and often spiral, case secreted or constructed by many annelids, crustaceans, insects, and other animals, for protection or concealment. See Illust. of Tubeworm.
  • noun One of the siphons of a bivalve mollusk.
  • noun (Elec. Railways), Chiefly Eng. A tunnel for a tube railway; also (Colloq.), a tube railway; a subway.
  • noun a tube of very fine bore. See Capillary.
  • noun (Steam Boilers) a tube which forms a flue.
  • noun (Zoöl.) Same as Tubipore.
  • noun (Zoöl.) one of the ambulacral suckers of an echinoderm.


from The American Heritage® Dictionary of the English Language, 4th Edition

[French, from Old French, from Latin tubus.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Middle French tube, from Latin tubus ("tube, pipe").


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  • When an ovum is matured, it escapes from the ovary into the narrow tube referred to, called the _Fallopian tube_, and passes down into the cavity of the uterus.

    Plain Facts for Old and Young John Harvey Kellogg 1897

  • It is passed down a tube that we call the _food tube_.

    The Child's Day Woods Hutchinson 1896

  • The _middle ear_, it will be seen, is a drum with its stretched membrane like any other drum, and it too has a communication with the exterior air through a tube, the _Eustachian tube_, which leads from the drum into the back part of the throat.

    Voice Production in Singing and Speaking Based on Scientific Principles (Fourth Edition, Revised and Enlarged) Wesley Mills 1881

  • The doctors were also asked whether other issues had led them to recommend the heart test — called a cardiac catheterization — during which a thin tube is threaded to the heart to check how well it is working and to look for disease.

    1 in Four Doctors Order Medical Tests Out of Fear of Getting Sued | Impact Lab 2010

  • The tube is a catheter (a thin tube) placed into the cecum, the first part of the large bowel (in the lower right abdomen).

    Percutaneous Cecostomy Tube Placement 2010

  • This test usually confirms the diagnosis. cardiac catheterization – a thin tube is inserted into the heart through a vein and/or artery in either the leg or through the umbilicus (“belly button”)

    Tricuspid Atresia 2010

  • Diagnosis may also include: chest X-ray electrocardiogram (ECG) – a record of the electrical activity of the heart cardiac catheterization – a thin tube is inserted into the heart through a vein and/or artery in either the leg, the neck, or through the umbilicus (“belly button” - used in newborns only). cardiac MRI

    Mitral Stenosis, Mitral Regurgitation and Mitral Valve Prolapse 2010

  • Cardiac magnetic resonance imaging (MRI) – detailed images of the heart produced by magnets cardiac catheterization – a thin tube is inserted into the heart through a large vein and/or artery in either the side of the neck, or groin

    Cardiomyopathy 2010

  • More rarely, cardiaccatheterization will be required: a thin tube is inserted into the heart through a vein and/or artery in either the leg or through the umbilicus (“belly button”).

    Ebstein’s Anomaly of the Tricuspid Valve 2009

  • Dar – For a tin tube is inserted for the passage of urine.

    The Book of The Thousand Nights And A Night 2006


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  • An endotracheal tube, a breathing tube placed down someone's throat into their windpipe.

    Also, to put one in a patient. "He couldn't keep up his sats, so we had to tube him."

    January 26, 2008

  • In the website "Riptionary. Surf Lingo Lexicon": "The cylindrical vortex or cone shaped hole created when a wave lip pitches out far and clean enough to create a space between the wave and the lip.". Link:

    November 21, 2010