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noun \ˈtüb, ˈtyüb\

Simple Definition of tube

  • : a long, hollow object that is used especially to control the flow of a liquid or gas

  • : an object shaped like a pipe

  • : a soft, long, narrow container that has a small opening at one end and that contains a soft material which can be pushed out by squeezing

Source: Merriam-Webster's Learner's Dictionary

Full Definition of tube

  1. 1 :  any of various usually cylindrical structures or devices: asa :  a hollow elongated cylinder; especially :  one to convey fluidsb :  a soft tubular container whose contents (as toothpaste) can be removed by squeezingc (1) :  tunnel (2) British :  subway bd :  the basically cylindrical section between the mouthpiece and bell that is the fundamental part of a wind instrument

  2. 2a :  a slender channel (as a fallopian tube or a pollen tube) within a plant or animal body :  ductb :  the narrow basal portion of a corolla with united petals or a calyx with united sepals

  3. 3 :  inner tube

  4. 4a :  electron tube; especially :  vacuum tubeb :  cathode-ray tube; especially :  a television picture tubec :  television

  5. 5 :  an article of clothing shaped like a tube <a tube top> <tube socks>

tubed play \ˈtübd, ˈtyübd\ adjective
tubelike play \ˈtüb-ˌlīk, ˈtyüb-\ adjective
down the tube or down the tubes
  1. :  into a state of collapse or deterioration

Examples of tube in a sentence

  1. She was breathing oxygen through a tube.

  2. <watched the liquid move through the tube between the flasks and recorded the movement in his chemistry notebook>

Origin of tube

French, from Latin tubus; akin to Latin tuba trumpet

First Known Use: 1651

Rhymes with tube

TUBE Defined for Kids


noun \ˈtüb, ˈtyüb\

Definition of tube for Students

  1. 1 :  a long hollow cylinder used especially to carry fluids

  2. 2 :  a long soft container whose contents (as toothpaste or glue) can be removed by squeezing

  3. 3 :  a slender channel within a plant or animal body :  duct

  4. 4 :  a hollow cylinder of rubber inside a tire to hold air

  5. 5 :  electron tube

  6. 6 :  television 2

tubelike \ˈtüb-ˌlīk, ˈtyüb-\ adjective

Medical Dictionary



noun \ˈt(y)üb\

Medical Definition of tube

  1. 1:  a slender channel within a plant or animal body :  duct—see bronchial tube, eustachian tube, fallopian tube

  2. 2a:  an often complex piece of laboratory or technical apparatus usually of glass and commonly serving to isolate or convey a product of reaction <a distillation tube>b:  test tube

  3. 3:  a soft tubular container whose contents (as toothpaste) can be dispensed by squeezing

  4. 4:  a hollow cylindrical device (as a cannula) used for insertion into bodily passages or hollow organs for removal or injection of materials



transitive verb

Medical Definition of tube

tubed; tubing

  1. :  to furnish with, enclose in, or pass through a tube <the patient is then anesthetized…and tubedAnesthesia Digest>

Seen and Heard

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the range of perception or understanding

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