The Collaborative International Dictionary of English v.0.48:
Chef \Chef\, n. [F.] 1. A chief or head person. [1913 Webster] 2. The head cook of large establishment, as a club, a family, etc. [1913 Webster] 3. (Her.) Same as Chief. [1913 Webster]WordNet (r) 3.0 (2006):
chef n 1: a professional cook