\ ˈbēm How to pronounce beam (audio) \

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

The blanket will be 14 to 18 feet tall and about 250 feet long, made of a composite polyvinyl chloride material, and supported by steel I-beams dug into the ground. Phil Diehl,, "Work starts on Coaster station improvements," 5 May 2018 The gate to their property is open, leading to the house, with its wooden beams and rustic charm, a swing set, outdoor fireplace and a pasture stocked with chickens and cows. Greg Bishop,, "Why Jake Locker Walked Away From Football—and Why He Doesn’t Miss It," 18 Apr. 2018 The other thing to remember here is that few ever seem to really completely leave Trump's orbit once they've been caught in his tractor beam. Z. Byron Wolf, CNN, "Trump's very small (and shrinking) inner circle," 29 Mar. 2018 The outside columns are 18 inches wide, the building's corners stand 180 inches tall, there's an 18 inch I-beam supporting the building's roof — the list goes on. Jessica Boehm, azcentral, "Effort to save Phoenix's first Orthodox Jewish synagogue reveals forgotten history," 23 Mar. 2018 Builders say the island’s mostly brick and concrete buildings risk collapsing in earthquakes because of soft soil and reliance on columns of rebar inside walls rather than steel I-beams for structural support. Ralph Jennings,, "It took a deadly earthquake to get Taiwan's attention, but now it's demanding safer buildings," 9 Mar. 2018 Like the sun breaking the horizon, her smile beams in the dark movie theater. Jeneé Osterheldt, kansascity, "‘Black Panther’ is so powerful, it could change Hollywood forever," 13 Feb. 2018 Built on rubble from the 1925 earthquake, the industrial building now hosts wineries, breweries, restaurants, and an artisanal craft collective beneath its wood and steel beams. Sunset, "Santa Barbara Guidebook: What to See & Do Now," 22 Jan. 2018 New York City is set to get a new radiation-treatment center, nearly a decade in the making, that uses proton beams to treat cancerous tumors. Melanie Grayce West, WSJ, "New York’s First Proton Therapy Center to Open in July," 16 May 2019

Recent Examples on the Web: Verb

The three-bedroom, two-and-a-half bathroom home has gorgeous vaulted, beamed ceilings and even features five (five!) fireplaces. Elizabeth Gulino, House Beautiful, "Jeff Bridges is Selling His Montecito Home For $8 Million," 23 May 2019 The Prince and first-time father was beaming and clearly thrilled about the arrival of his son. Elizabeth Angell, Town & Country, "Prince Harry Just Spoke About Witnessing Meghan Markle Give Birth to Their Son," 6 May 2019 To get a clear shot, take photos in the morning before the mid-day sun starts beaming and the crowds are at their peak. Amanda Garrity, Good Housekeeping, "Why Spending Christmas Day at Disney World Is Truly as Magical as It Sounds," 20 Dec. 2018 Location: Lincoln, Massachusetts Price: $1,495,000 A soaring post-and-beam midcentury getaway is on the market in Lincoln, Massachusetts. Lauren Ro, Curbed, "Light-filled midcentury home overlooking pond wants $1.5M," 2 May 2018 But beauty bloggers are swearing by it as primer to create radiance that beams out from below foundation. Marci Robin, Allure, "Huda Beauty Debuts “Liquid Pantyhose” Body Highlighter With a Whopping 30 Percent Shimmer," 28 Apr. 2019 There's also a 60GHz 802.11ad Wi-Fi dock that can wirelessly beam your gaming content to a TV. Ron Amadeo, Ars Technica, "Asus’ insane gaming phone has 3 USB ports, clip-on cooling fan," 4 June 2018 By year’s end, startup OneWeb aims to launch the first of a constellation of 900 little, low-orbit satellites beaming high-speed internet. Troy Farah, Discover Magazine, "The Web, Worldwide," 19 Oct. 2018 On July 4, 1957, at approximately 9:05 a.m., a voice beamed out of transistor radios across New York City. Michael S. Rosenwald, Washington Post, "‘Awe-inspiring’: Listen to Sen. John F. Kennedy read the Declaration of Independence," 4 July 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

9 Jun 2019

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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 How to pronounce beam (audio) \

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 How to pronounce beam (audio) \

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

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


to move with exaggerated bouncy motions

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