laser

Laser began as LASER, an acronym for 'light amplification by stimulated emission of radiation,' coined by American physicist Gordon Gould in 1957. It was borrowed from this English acronym, and in Latin, 'laser' itself was an existing word (radius meaning ray/beam is part of the underlying phrase, via radiatio).

Originally the device was called an optical maser; the acronym LASER was coined in 1957 to describe how it works, and it settled into everyday use as a lowercase common noun, 'laser.'

It shares roots with 'amplification' and 'radiation,' both pieces of the original phrase the acronym compresses, as well as 'stimulate' and 'emission.'