The Collaborative International Dictionary of English v.0.48:
Senor \Se*[~n]or"\, n. [Sp. Cf. Senior.] A Spanish title of courtesy corresponding to the English Mr. or Sir; also, a gentleman. [1913 Webster] SenyoraWordNet (r) 3.0 (2006):
Senor n 1: a Spanish title or form of address for a man; similar to the English `Mr' or `sir'