The Collaborative International Dictionary of English v.0.48:
Gallicism \Gal"li*cism\, n. [F. gallicisme.] A mode of speech peculiar to the French; a French idiom; also, in general, a French mode or custom. [1913 Webster]WordNet (r) 3.0 (2006):
Gallicism n 1: a word or phrase borrowed from French