raison d'être [ rey-zohn de-truh; French re-zawn de-truh ]
noun, plural rai·sons d'ê·tre [rey-zohnz de-truh; French re-zawn de-truh].
1. reason or justification for being or existence: Art is the artist's raison d'être.
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Origin: Borrowed into English from French around 1865–70
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