Meaning of LASER in English
n. a device that generates an intense beam of coherent monochromatic radiation in the infrared, visible, or ultraviolet region of the electromagnetic spectrum, by stimulated emission of photons from an excited source.
[ light amplification by stimulated emission of radiation: cf. MASER ]
Concise Oxford English dictionary. Краткий оксфордский словарь английского языка. 2012