Dictionary.com
Thesaurus.com

Gallicism

American  
[gal-uh-siz-uhm] / ˈgæl əˌsɪz əm /
Or gallicism

noun

  1. a French idiom or expression used in another language, as Je ne sais quoi when used in English.

  2. a feature that is characteristic of or peculiar to the French language.

  3. a custom or trait considered to be characteristically French.


Gallicism British  
/ ˈɡælɪˌsɪzəm /

noun

  1. a word or idiom borrowed from French

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of Gallicism

First recorded in 1650–60; from French gallicisme; Gallic, -ism