Definition - An idiom or mode of expression belonging to the French language, especially one that is used by a speaker or writer in some other language.

Example -
Kissinger engineered the coup d'état.

Etymology -
The word derives from the Latin Gallicus, pertaining to Gaul or the Gauls.

Oxford English Dictionary -
Its first citation is from 1656:
"Gallicism, the form of speech, or custom of the French."
(Blount Glossogr )

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