What Does It Mean?

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From our dictionary:
on•o•mat•o•poe•ia

(on"u-mat"u-pē'u, -mä"tu-),
n.

1. the formation of a word, as cuckoo or boom, by imitation of a sound made by or associated with its referent.
2. a word so formed.
3. Rhet. the use of imitative and naturally suggestive words for rhetorical effect.