\ 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

On Friday, a worker was on the fourth deck welding an overhead steel beam to secure it in preparation for additional wood removal when a spark fell down, Kattoo said. Ann Zaniewski, Detroit Free Press, "Boblo boat Ste. Claire owners launch fundraising campaign to rebuild," 10 July 2018 Lidar sends out laser beams to map the road ahead and guide the car, and Strobe’s version is smaller, cheaper and can see farther ahead than GM’s existing equipment. Fortune, "Who’s Winning the Self-Driving Car Race?," 31 May 2018 In 2003, the BBC funded a massive expedition using satellites and 600 sonar beams but didn’t find any signs of the beast. Jason Daley, Smithsonian, "DNA Survey of Life in Loch Ness Will Hunt for Its Monster Resident," 29 May 2018 Lit by several beams of white light, the divers in wet suits and helmets are seen submerging themselves in the water and grabbing on to a metal dive line used to guide them through the winding channels of the six-mile cave. Rebecca Tan, Washington Post, "New video from Thai navy shows the scene inside Tham Luang cave during dramatic rescue," 11 July 2018 Attached are 10 photos from inside the cave of boys in soccer uniforms smiling and posing for photos, lit by the beam of a flashlight. Kaitlyn Schallhorn, Fox News, "Thai soccer coach, 25-year-old former Buddhist monk, hailed 'hero' for keeping boys alive," 10 July 2018 The company name was first inspired by the idea of two light beams of different colors overlapping to create a third color. Diane Mastrull,, "Software-guided B2B partnerships are the aim of Bob Moore's new Crossbeam," 9 July 2018 The diagonal beams are like a scaffold that holds in place the condominiums and offices and elevator stacks within. John King,, "New nimble, frisky SoMa tower fits neatly into surroundings," 6 July 2018 The Japanese-style fire pit and tin range hood are custom, the floor lamp is from the ’70s, the sisal carpet is by Stark, the ceiling beams are Douglas fir, and a series of color lithographs from Japan are displayed along the pine wainscoting. Vanessa Lawrence And ·, ELLE Decor, "How a Japanese House in Upstate New York Found Its Zen," 19 Apr. 2018

Recent Examples on the Web: Verb

And, on the bright side, there was plenty of room for one beaming couple to slow-dance. Milwaukee Journal Sentinel, "Best and worst of Summerfest Day 9: Janelle Monáe, Flaming Lips, BØRNS, Judah & the Lion and more," 7 July 2018 This is going to sound a little crazy, but researchers have figured out ways to beam low levels of power through the air. Geoffrey Fowler,, "Future Phones: They Fold Like Napkins, Have 9 Cameras, Charge Over Thin Air," 6 July 2018 Big pictures of Trump, Kim, beaming on the front page. Margaret Hartmann, Daily Intelligencer, "Trump and Kim Stir Confusion About What They Actually Agreed To," 13 June 2018 Big pictures of Trump, Kim, beaming on the front page. Euan Mckirdy, CNN, "North Korean media praises Trump in 'meeting of the century'," 13 June 2018 While Prince Harry gave a welcoming address at the event—a garden party honoring his father, Prince Charles—his family, including his new wife, beamed beside him. Erica Gonzales, Harper's BAZAAR, "Meghan Markle Had a Gigglefest with Her In-Laws," 22 May 2018 At least five trucks have slammed into the warning beams set up in December in front of the 7-foot-high Concord Covered Bridge, which was burned down durng the Civil War but rebuilt, WABE reports. Fox News, "Historic covered bridge threatened by GPS directions," 1 May 2018 The Pale Blue Dot was the final picture beamed back to Earth by Voyager 1, now the most distant thing made by humans and the first craft to cross into interstellar space. Ben Guarino, ajc, "These record-breaking pictures were taken by the farthest camera from Earth," 9 Feb. 2018 When the last diploma was handed out, the group assembled at the front of the room, beaming, their work cut out for them. Mike Newall,, "Meet the Healers, young black men turning their trauma into something that helps others | Mike Newall," 13 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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Phrases Related to beam

full beam

laser beam

off beam

Statistics for beam

Last Updated

1 Sep 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).


alleviating pain or harshness

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