From WordNet (r) 3.0 (2006) [wn]:
chef
n 1: a professional cook
From The Collaborative International Dictionary of English v.0.48 [gcide]:
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]