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noun \ˈbēm\

Simple Definition of beam

  • : a line of light coming from a source (such as the sun or a headlight)

  • : a line of energy, particles, etc., that cannot be seen

  • : a long and heavy piece of wood or metal that is used as a support in a building or ship

Full Definition of beam

  1. 1 a :  a long piece of heavy often squared timber suitable for use in construction b :  a wood or metal cylinder in a loom on which the warp is wound c :  the part of a plow to which handles, standard, and coulter are attached d :  the bar of a balance from which scales hang e :  one of the principal horizontal supporting members (as of a building or ship) <a steel beam supporting a floor>; also :  boom, spar <the beam of a crane> f :  the extreme width of a ship at the widest part g :  an oscillating lever on a central axis receiving motion at one end from an engine connecting rod and transmitting it at the other

  2. 2 a :  a ray or shaft of light b :  a collection of nearly parallel rays (as X rays) or a stream of particles (as electrons) c :  a constant directional radio signal transmitted for the guidance of pilots; also :  the course indicated by a radio beam

  3. 3 :  the main stem of a deer's antler

  4. 4 :  the width of the buttocks

on the beam
  1. 1 :  following a guiding beam

  2. 2 :  proceeding or operating correctly

Examples of beam

  1. a bright beam of light

  2. We saw the beams from their flashlights.

  3. the building's steel support beams

Origin of beam

Middle English beem, from Old English bēam tree, beam; akin to Old High German boum tree

First Known Use: before 12th century

Other Wood Production Terms




Simple Definition of beam

  • : to smile happily

  • : to say (something) while smiling happily

  • : to send out beams of light or energy

Full Definition of beam

  1. transitive verb
  2. 1 :  to emit in beams or as a beam

  3. 2 :  to support with beams

  4. 3 a :  to transmit especially by satellite :  broadcast b :  to transmit (data) electronically c :  to direct to a particular audience

  5. intransitive verb
  6. 1 :  to send out beams of light

  7. 2 :  to smile with joy

Examples of beam

  1. She beamed as she told us the good news.

  2. They stood beaming with satisfaction.

  3. We're getting married! he beamed.

  4. The sun beamed its light through the window.

  5. Pictures of the distant planet were beamed back to the Earth.

15th Century

First Known Use of beam

15th century

Medical Dictionary


noun \ˈbēm\

Medical Definition of beam

  1. 1:  a ray or shaft of light

  2. 2:  a collection of nearly parallel rays (as X-rays) or a stream of particles (as electrons)

Seen and Heard

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February 8, 2016

to clear from accusation or blame

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