The definition of adieu is a French word used to wish someone well when you are leaving.
(noun)Saying goodbye and leaving is an example of adieu.
See adieu in Webster's New World College Dictionary
See adieu in American Heritage Dictionary 4
interjection
Origin:
Origin: Middle English
Origin: , from Old French a dieu, (I commend you) to God
Origin: : a, to (from Latin ad; see ad-)
Origin: + Dieu, God (from Latin deus; see dyeu- in Indo-European roots)
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