laser

noun, often attributive la·ser \ ˈlā-zər \

|Updated on: 7 Jul 2018

Definition of laser

1 : a device that utilizes the natural oscillations of atoms or molecules between energy levels for generating a beam of coherent electromagnetic radiation usually in the ultraviolet, visible, or infrared regions of the spectrum; also : the beam of coherent radiation itself

The cesium fluoresced. This told them they had the necessary population of excited atoms to produce a laser.
—Nick Taylor

2 : something resembling a laser beam in accuracy, speed, or intensity

threw a laser into the end zone

a laser stare

See laser defined for English-language learners

See laser defined for kids

Examples of laser in a Sentence

doctors using a laser to perform delicate eye surgery

Recent Examples of laser from the Web

Another, in Cambridge, designs satellites that use lasers to speed data communications.

— hiawatha bray, BostonGlobe.com, "New England stakes its claim in New Space," 2 July 2018
For the study, published in the American Research Journal of Pharmacy, the researchers used lasers of different colors to gauge the physical and emotional responses to light and color of participants with various ailments.

— caroline biggs, New York Times, "Living in Color," 22 June 2018
So the study team assembled a database of skull and teeth dimensions for the four living genera of gibbons, using lasers to measure a total of 789 teeth from 279 individuals, as well as 477 skulls.

— National Geographic, "Ancient Royal Tomb Yields Strange New Ape Species," 21 June 2018
Most of these systems used radar (a few early systems used lasers) to detect the position and speed of the car ahead of it and maintain a safe following distance.

— timothy b. lee, Ars Technica, "Why emergency braking systems sometimes hit parked cars and lane dividers," 8 June 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
The Cygnus holds a student cement-mixing experiment, as well as an atom-cooling chamber from NASA's Jet Propulsion Laboratory that uses lasers to get temperatures colder than even space itself.

— OrlandoSentinel.com, "NASA shipper Orbital ATK launches space-station supplies," 21 May 2018
The projector uses three lasers of red, blue, and green, and the projection is bright enough to be seen outdoors.

— thuy ong, The Verge, "This projector smartwatch turns your arm into a terrible touchscreen," 27 Apr. 2018
The seismic waves from a nearby earthquake will deform the cable minutely, leaving the returning light slightly out of phase with the light emitted by the laser.

— The Economist, "Submarine cables could be repurposed as earthquake detectors," 16 June 2018

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

Origin and Etymology of laser

light amplification by stimulated emission of radiation

NEW! Time Traveler

First Known Use: 1957

in the meaning defined at sense 1

See Words from the same year

laser

verb

Definition of laser

lasered; lasering; lasers

transitive verb

: to subject to the action of a laser : treat with a laser

Recent Examples of laser from the Web

Then there's Skin Laundry, a global chain with locations in Los Angeles, London, and Hong Kong, which lasers your face clean in 15 minutes—something my crammed schedule appreciates.

— garrett munce, GQ, "I Got a Facial and Now I'm a Golden God," 8 Apr. 2018
Louisville basketball's Myisha Hines-Allen selected 19th in WNBA draft Shannon Hall INDIANAPOLIS — The pass was lasered right to Myisha Hines-Allen, but too fast for the rookie to handle.

— danielle lerner, The Courier-Journal, "Louisville basketball could have another breakout rookie in the pros," 25 May 2018
The women, weaponized in power heels, stand equally vertical, meeting the men laser eye to laser eye.

— james wolcott, HWD, "Confessions of a Suits Fan: Why the Legal Drama That Launched Meghan Markle Works," 27 Apr. 2018
Satellite dishes mark the main gate of Fort Gordon, eggshell white and lasering up at the moon.

— matt gallagher, WIRED, "Army of 01101111: The Making of a Cyber Battalion," 27 Mar. 2018
Missouri’s first touchdown came when Lock lasered the ball to J’Mon Moore along the left sideline midway through the second quarter.

— aaron reiss, kansascity, "Missouri QB Drew Lock, offense put up some impressive numbers in loss to Kentucky," 7 Oct. 2017
Two plays later, facing third and 18, Mahomes lasered a pass toward the left sideline that was both nearly a spectacular completion to Seantavius Jones and perhaps a step from being a pick-six for defensive back Kalan Reed.

— vahe gregorian, kansascity, "Next step in Mahomes’ development: Break glass only in case of emergency," 31 Aug. 2017
Four days later, Darvish debuted in his new team’s gray and blue road uniforms, lasering fastballs and looping curves for seven shutout innings.

— robert o'connell, The Atlantic, "The Dodgers Aim for History—and a Championship," 9 Aug. 2017
Now, according to Jill Kargman, creator of Bravo’s scripted series Odd Mom Out, which studies and satirizes the Upper East Side, the Gold Coast is obsessed with lasering their vaginal wall.

— katie van syckle, The Cut, "Vaginal Tightening Is Apparently a Hot Trend on the Upper East Side," 14 July 2017

First Known Use of laser

1978

in the meaning defined above

See Words from the same year

NEW! Time Traveler

LASER Defined for English Language Learners

laser

noun

Definition of laser for English Language Learners

: a device that produces a narrow and powerful beam of light that has many special uses in medicine, industry, etc.

LASER Defined for Kids

laser

noun la·ser \ ˈlā-zər \

Definition of laser for Students

: a device that produces a very powerful beam of light

Medical Dictionary

laser

noun la·ser \ ˈlā-zər \

medical Definition of laser

: a device that utilizes the natural oscillations of atoms or molecules between energy levels for generating coherent electromagnetic radiation usually in the ultraviolet, visible, or infrared regions of the spectrum