1

laser

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

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

Examples of laser in a Sentence

  1. doctors using a laser to perform delicate eye surgery

Recent Examples of laser from the Web

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


2

laser

verb

Definition of laser

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

Recent Examples of laser from the Web

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.

First Known Use of laser

1978



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

1

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

2

laser

transitive verb

medical Definition of laser

:to subject to the action of a laser :treat with a laser
  • cutting a corneal flap to remove tissue and then lasering the area under it
  • —Jenny Manzer


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