Definition -
(1) The forming of a word by imitating a sound that is associated with the thing being labelled.
(2) This behaviour as a word formation process.
(3) A word formed by this process.

Example -
In English bees buzz, birds chirp, and Mormons murmur. Sometimes different peoples hear the same things differently. Thus in English, dogs say bow wow; in Korean they say mung mung; and in Chinese they say wang wang.

Etymology -
It derives via Late Latin from the Greek onomatopoiia, the making of a name or word by imitating the thing's sound (from the Greek onoma, word or name + poiein, make).

Oxford English Dictionary -
Its first citation is from 1577:
"Onomatopeia, when we invent, devise, fayne, and make a name intimating the sound of that it signifieth, as hurlyburly, for an uprore and tumultuous stirre."
(Peacham Gard. Eloquence)

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