The Collaborative International Dictionary of English v.0.48:
Restaurateur \Re`stau`ra`teur"\ (r?`st?`r?`t?r"), n. [F.] The keeper of an eathing house or a restaurant. [1913 Webster]WordNet (r) 3.0 (2006):
restaurateur n 1: the proprietor of a restaurant [syn: restaurateur, restauranter]