Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Medical
  • Scrabble
  • Spanish Central
  • Learner's Dictionary


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

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
tube·like play \ˈtüb-ˌlīk, ˈtyüb-\ adjective
down the tube or down the tubes
  1. :  into a state of collapse or deterioration

Examples of tube

  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

Seen and Heard

What made you want to look up tube? Please tell us where you read or heard it (including the quote, if possible).


February 8, 2016

to clear from accusation or blame

Get Word of the Day daily email!


Take a 3-minute break and test your skills!


Which of the following refers to thin, bending ice, or to the act of running over such ice?

duvet pince-nez kittly-benders spindrift
Name That Thing

10 quick questions: hear them, spell them, and see how your skills compare to the crowd.


Test Your Knowledge - and learn some interesting things along the way.