\ 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

Synonyms: Verb

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Examples of beam in a Sentence

Noun a bright beam of light We saw the beams from their flashlights. the building's steel support beams Verb 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 liberal organization Media Matters recently reported that in 2018, Greene in a Facebook post reiterated a QAnon claim that deadly wildfires in California may have been caused by a laser beam from space. Todd Spangler, Detroit Free Press, "Fred Upton votes with Dems to strip Marjorie Taylor Green of committee seats," 5 Feb. 2021 The Monochrome features aromas and flavors of mock orange flowers, saline and lemon curd on toast, all delivered by a high acid laser beam. Michael Alberty | For The Oregonian/oregonlive, oregonlive, "6 Champagnes we deserve as we kick 2020 to the curb," 22 Dec. 2020 The final construction beam atop the 31-story office tower at 1105 West Peachtree Street in Midtown was recently installed and the project will be finished on time, according to developer Selig Enterprises. Andy Peters, ajc, "Tallest tower since recession defies pandemic, nears completion," 25 Jan. 2021 Instead of a solid beam, this type of laser bombards the target area with a polka-dot pattern that damages less tissue and speeds up recovery. Julie Ricevuto, Allure, "The Science of Beauty: The Complete Guide to Laser Treatments for Hair and Skin," 30 Dec. 2020 To measure the telltale magnetism, g-2 researchers fire a beam of muons (or, to be more precise, their antimatter counterparts) into a 15-meter-wide circular particle accelerator. Adrian Cho, Science | AAAS, "The cloak-and-dagger tale behind this year’s most anticipated result in particle physics," 27 Jan. 2021 These subs aren't large—they're only 222 feet long with a beam of 28 feet and a crew of up to 55. Kyle Mizokami, Popular Mechanics, "Watch This Wild Ride Through the Guts of a Secret Submarine," 27 Jan. 2021 Laser hair removal is a medical procedure that uses a concentrated beam of light to remove unwanted hair. Julie Ricevuto, Allure, "The Science of Beauty: The Complete Guide to Laser Treatments for Hair and Skin," 30 Dec. 2020 The prizewinners studied weak-force interactions at high energies by creating a beam of neutrinos, which do not interact through the strong force but do so by the weak force. Washington Post, "Jack Steinberger, Nobel laureate in physics, dies at 99," 17 Dec. 2020 Recent Examples on the Web: Verb Sunday brought a story so positive and so beautiful that every resident of north Minneapolis — and this entire state, actually — should beam until their faces hurt from smiling. Star Tribune, "Tyler Johnson, Super Bowl champion, celebrated as 'mirror for these kids' in north Minneapolis," 8 Feb. 2021 Each tag will collect data on its wearer’s position, physiology and microclimate, sending it to a receiver on the International Space Station, which will beam it back down to computers on the ground. New York Times, "Skip to site index," 12 Jan. 2021 The company is also pressing ahead with another outrageously difficult project — a plan to flood Earth orbit with thousands of satellites that would beam Internet signals to ground stations, connecting rural areas to broadband. Washington Post, "2021 could be a huge year for space. Here’s what’s to come from NASA, Elon Musk, Richard Branson and Jeff Bezos.," 30 Dec. 2020 Founded in 2016, the company has launched two synthetic aperture radar (SAR) satellites that beam radio energy at the Earth from orbit, and decode its reflection back with a novel antenna design. Tim Fernholz, Quartz, "A startup is teaching the US military how to make space radar cheap," 17 Dec. 2020 The right kind of solar panels paired with storage could periodically beam power to specific places without losing notable energy. Caroline Delbert, Popular Mechanics, "The Air Force Is Building a Spacecraft That Will Beam Solar Power to Earth," 30 Dec. 2020 Some turned out to come from previously unknown astronomical sources such as pulsars, the rapidly rotating corpses of dead stars that beam radio waves into the cosmos. Nadia Drake, Science, "Alien hunters detect mysterious radio signal from nearby star," 18 Dec. 2020 While glass-panel costs have fallen considerably, sunlight is an intermittent and variable power supply thanks to nighttime, clouds, regional intensity and seasonality (unless an Elon Musk figure can beam solar power from space). William Levin, National Review, "We Have Time to Prevent Climate Change," 15 Dec. 2020 Installing reflective surfaces on rooftops or roads, which can help beam sunlight away, is another potential tool. Chelsea Harvey, Scientific American, "Climate Inequality Exists in U.S. Cities and Has Deep Racist Roots," 10 Dec. 2020

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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Time Traveler for beam

Time Traveler

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

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Statistics for beam

Last Updated

27 Feb 2021

Cite this Entry

“Beam.” Dictionary, Merriam-Webster, Accessed 2 Mar. 2021.

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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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