First Known Use: before 12th century
Dictionary
1beam
noun \ˈbēm\
: 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
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
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
: the main stem of a deer's antler
4
: the width of the buttocks
— on the beam
1
: following a guiding beam
2
: proceeding or operating correctly
See beam defined for English-language learners
See beam defined for kids
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Origin of BEAM
Middle English beem, from Old English bēam tree, beam; akin to Old High German boum tree
2beam
verb
: to smile happily
: to say (something) while smiling happily
: to send out beams of light or energy
Full Definition of BEAM
transitive verb
1
: to emit in beams or as a beam
2
: to support with beams
3
a : to transmit especially by satellite : broadcast b : to transmit (data) electronically c : to direct to a particular audience
intransitive verb
1
: to send out beams of light
2
: to smile with joy
See beam defined for English-language learners
First Known Use of BEAM
15th century
BEAMS Defined for Kids
1beam
noun \ˈbēm\
Definition of BEAM for Kids
1
: a long heavy piece of timber or metal used as a main horizontal support of a building or a ship <a ceiling beam>
2
: a ray of light
3
: a radio wave sent out from an airport to guide pilots
2beam
verb
beamedbeam·ing
Definition of BEAM for Kids
1
: to send out beams of light <Sunlight was beaming through the window.>
2
: to smile with joy <She beamed as she told us the good news.>
3
: to aim a radio broadcast by use of a special antenna
Medical Dictionary
beam
noun \ˈbēm\
Medical Definition of BEAM
1
: a ray or shaft of light
2
: a collection of nearly parallel rays (as X-rays) or a stream of particles (as electrons)
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