\ˈbēm \

Definition of beam 

(Entry 1 of 2)

1a : a long piece of heavy often squared timber suitable for use in construction

b weaving : a wood or metal cylinder in a loom on which the warp (see warp entry 1 sense 1a) 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 nautical : the extreme width of a ship at the widest part

g engines : an oscillating lever on a central axis receiving motion at one end from an engine connecting rod and transmitting it at the other

2a : a ray or shaft of light beams from the searchlights

b : a collection of nearly parallel rays (such as X-rays) or a stream of particles (such 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 … immensely broad in the beam— Ann Bridge

on the beam

1 : following a guiding beam

2 : proceeding or operating correctly


beamed; beaming; beams

Definition of beam (Entry 2 of 2)

transitive verb

1 : to emit in beams or as a beam (see beam entry 1 sense 2) The sun beamed its light through the window.

2 : to support with beams (see beam entry 1 sense 1) The house was beamed with heavy timbers.

3a : to transmit especially by satellite : broadcast … the 90-minute show was beamed to more than 200 countries and territories around the world.TV Guide

b : to transmit (data) electronically beaming images of the planet back to Earth The amount of data beamed over fiber-optic networks is rising exponentially every year, yet only 0.1% of fiber capacity is in use.— Leslie Cauley especially : to transmit (data) wirelessly Infrared connectivity enables users to work collaboratively on documents without having to log on to the network, and for quickly "beaming" data between different devices (for example, between two notebooks, or between a notebook and a printer, without a need for a cable). Newsweek

c : to direct to a particular audience a commercial beamed at middle-class voters

intransitive verb

1 : to send out rays of light Sunlight beamed through the window.

2 : to smile with joy The bride was beaming.

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Synonyms for beam

Synonyms: Noun

ray, shaft

Synonyms: Verb

radiate, ray, shine

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Examples of beam in a Sentence


a bright beam of light We saw the beams from their flashlights. the building's steel support beams


She beamed as she told us the good news. They stood beaming with satisfaction. “We're getting married!” he beamed. The sun beamed its light through the window. Pictures of the distant planet were beamed back to the Earth.
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Recent Examples on the Web: Noun

In the most recent incident in Djibouti, two American pilots flying a C-130 turboprop experienced minor eye injuries after being exposed to the laser beam. Jeremy Page, WSJ, "American Military Aircraft Targeted By Lasers in Pacific Ocean, U.S. Officials Say," 21 June 2018 The coaster speeds through tunnels filled with visual effects from laser beams to a stretching Elastigirl. Scott Craven, azcentral, "Pixar Pier first look: Riding the Incredicoaster at California Adventure," 21 June 2018 Fajman said the new policy will have the machines placed on racks, a cable will connect the machines and be secured to a steel beam. Craig Lyons, Post-Tribune, "Training aims to stop poll workers' errors from disqualifying votes," 19 June 2018 The idea is to shine a high-quality laser beam through one of the optical fibres in the cable. The Economist, "Submarine cables could be repurposed as earthquake detectors," 16 June 2018 Lidar maps are created by flying over terrain and shooting laser beams at the surface to gather elevation data. Mark Collette, Houston Chronicle, "Hurricane ready? Houston, 21 states, can buy cheap flood insurance in minutes, company claims," 12 June 2018 Perching on a slender steel beam with nothing but the city streets far below him simply became a reality of the job. Patrick M. O'connell,, "At 80, ironworker who has dangled atop Chicago's tallest skyscrapers is still climbing," 9 June 2018 Tony’s presence serves as a strong support beam in Olivia’s life, even as it is revealed that Tony’s own life has its fair share of instability., "Tony & Olivia Are The Best 13 Reasons Why Pairing On-Screen & IRL," 27 May 2018 The wooden support beams were salvaged from a cheese factory auctioned in Wisconsin. Shonda Talerico Dudlicek, Elgin Courier-News, "Guide to outdoor dining in Chicago suburbs: Port Edward in Algonquin," 7 July 2018

Recent Examples on the Web: Verb

On the hallway bulletin board are pinned pictures of community events, the Carters beaming with locals. Michael Paterniti, GQ, "Jimmy Carter for Higher Office," 26 June 2018 The floor of the vestibule has decorative terra cotta floor tiles, foyer walls are lined with oak wainscoting, and the ceilings are open-beamed with decorative plaster moldings. Joanne Kempinger Demski, Milwaukee Journal Sentinel, "Tour for a cure: Architectural treasure is this year's Breast Cancer Showhouse," 18 May 2018 The antenna beams radio waves from Earth, which Juno’s transponder receives and sends back. Lee Billings, Scientific American, "Juno Peers Deep into Jupiter's Abyss to Reveal Weird Winds," 7 Mar. 2018 Some investigators walked up and down the roadway, their flashlight beams roving the ground, while others scoured the area around a garbage bin that had been knocked over in the middle of the street, its contents spilled onto the roadway. Laura Mcknight,, "NOPD investigating homicide after truck crashes into home in New Orleans East," 18 Jan. 2018 Now a new study, published in Nature, has tested the principle using a remarkably extreme astrophysical environment: a triple star system containing two white dwarfs and a pulsar (a rotating neutron star that beams radio waves). James Geach, Scientific American, "Triple-Star Test Shows Einstein Was Right, Again," 5 July 2018 His previous company, Aereo, provided a service that beamed television shows over the Internet, without paying retransmission fees to the broadcast networks. Hiawatha Bray,, "Boston Internet service Starry, aiming to take on its bigger rivals, raises $100 million," 5 July 2018 The same sun that burns you on the beach is the same sun that beams through your window during a traffic jam. Elizabeth Wellington,, "This sun-protective clothing line by a King of Prussia dermatologist is actually pretty cute | Elizabeth Wellington," 2 July 2018 As Hawking's ashes are being interred between the graves of Charles Darwin and Sir Isaac Newton at a memorial service Friday at Westminster Abbey, an antenna in Spain will beam his voice out into space, toward a black hole. Elizabeth Elkin And Brandon Griggs, CNN, "Stephen Hawking's voice will be beamed 3,500 light years into space," 14 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'beam.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of beam


before the 12th century, in the meaning defined at sense 1a


15th century, in the meaning defined at transitive sense 1

History and Etymology for beam


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


Middle English bemen, verbal derivative of bem, beem beam entry 1

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Phrases Related to beam

full beam

laser beam

off beam

Statistics for beam

Last Updated

13 Oct 2018

Look-up Popularity

Time Traveler for beam

The first known use of beam was before the 12th century

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More Definitions for beam



English Language Learners Definition of beam

 (Entry 1 of 2)

: 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



English Language Learners Definition of beam (Entry 2 of 2)

: to smile happily

: to say (something) while smiling happily

: to send out beams of light or energy


\ˈbēm \

Kids Definition of beam

 (Entry 1 of 2)

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


beamed; beaming

Kids Definition of beam (Entry 2 of 2)

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


\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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Comments on beam

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


one that holds something together

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