\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

Instead of delving into the details, let’s put it like this: the wavelength and intensity profile of a laser beam creates a pot that holds the BEC. Chris Lee, Ars Technica, "Donut-shaped BEC might be key to fault-protected quantum logic," 5 Nov. 2018 For horizontal aim, the most intense of the beam should be right of the vertical tapeline. Anthony Alaniz, Popular Mechanics, "How to Adjust Your Headlights," 27 Sep. 2018 With proton radiation therapy, the width and depth of the beam can be targeted more precisely to ensure maximum exposure to the tumor with minimal damage to healthy tissue. The Seattle Times, "Proton beams destroy brain tumors and give kids a chance," 13 Sep. 2018 Commercial firms also offer glare-resistant screens that may help reduce the effects of a laser beam. Gordon Lubold, WSJ, "Laser Beam Attacks Bedevil U.S. Military Pilots in Mideast," 17 Aug. 2018 The weapon, which would be mounted to an airplane, would disable fixed-wing or quadcopter drones with a beam of focused radiation. Russell Brandom, The Verge, "The Army is buying microwave cannons to take down drones in mid-flight," 7 Aug. 2018 Hard Rock has scheduled a July 9 ceremony for placement of the final beam. David Lyons,, "Guitar-shaped hotel tower nears top-off at Seminole Hard Rock in Hollywood," 21 June 2018 For example, state-of-the-art models still struggle to capture the flutter from large flapping motions at the end of a long beam—like gusting wind along the length of a diving board. Justin Webster, Scientific American, "Harnessing the Invisible Power of “Flutter”," 31 Mar. 2018 After applying to receive a piece of the towers that still remained, the Rotary club was given a piece of steel beam from the north tower. Brian Lisik/special To,, "Suspicious car in driveway reported to police: Medina Police Blotter," 13 Feb. 2018

Recent Examples on the Web: Verb

The little craft that could will continue to beam back new insights about the gas giant through 2021. Jason Daley, Smithsonian, "Jupiter’s Lightning Is More Earth-Like Than We Thought," 8 June 2018 De Souza, who had been brought into the courtroom in handcuffs along with two men detained by ICE, beamed at her lawyer, Adriana Lafaille, after the hearing. Maria Cramer,, "Federal judge accuses Homeland Security of breaking policy on detaining immigrants," 9 May 2018 In August 2014, Philly purchased Quince Imaging’s cutting-edge, projection-mapping technology to be beamed onto the Wells Fargo Center court. Jake Fischer,, "Liberty At Last: The Process Behind the 76ers' Bell-Ringing Ceremony," 4 May 2018 Satellite trucks and spotlights filled nearly every vacant plot of land as reporters beamed their live shots at all hours of the day. Cory Shaffer,, "Ariel Castro's former neighbors on Seymour Avenue are tired of being pointed at," 4 May 2018 The former Alabama forward emphatically said yes as Bozeman beamed looking up at his new fiancee. John Talty,, "Watch Bradley Bozeman propose to girlfriend after national championship," 9 Jan. 2018 This will be your future, the devil’s eyes beam up at her. Karen Russell, The New Yorker, "Orange World," 4 June 2017 Meanwhile, illustrator Eugene Yelchin offers beautiful, woodcut-like drawings depicting Brangwain’s dispatches from the goblin kingdom, extracted from his thoughts and beamed back to the elves via a magic spell. Constance Grady, Vox, "We read all 25 National Book Award finalists for 2018. Here’s what we thought.," 15 Nov. 2018 Measuring a practical 1,980 square feet, the home features classic post and beam construction designed by Richard Pleger, a colleague of RIchard Netura in Southern California. Megan Barber, Curbed, "Renovated midcentury near Las Vegas wants $437K," 2 Nov. 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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Statistics for beam

Last Updated

8 Dec 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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More from Merriam-Webster on beam

Rhyming Dictionary: Words that rhyme with beam

Thesaurus: All synonyms and antonyms for beam

Spanish Central: Translation of beam

Nglish: Translation of beam for Spanish Speakers

Britannica English: Translation of beam for Arabic Speakers Encyclopedia article about beam

Comments on beam

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a soft lustrous wool fabric with mohair

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