laser
Pronunciation: /ˈleɪzə/
noun
- a device that generates an intense beam of coherent monochromatic light (or other electromagnetic radiation) by stimulated emission of photons from excited atoms or molecules. Lasers are used in drilling and cutting, alignment and guidance, and in surgery; the optical properties are exploited in holography, reading barcodes, and in recording and playing compact discs.

Origin:
1960s: acronym from light amplification by stimulated emission of radiation, on the pattern of maser

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