The Collaborative International Dictionary of English v.0.48:

Chevalier \Che`va*lier"\, n. [F., fr. LL. caballarius. See
   Cavaller.]
   1. A horseman; a knight; a gallant young man. "Mount,
      chevaliers; to arms." --Shak.
      [1913 Webster]

   2. A member of certain orders of knighthood.
      [1913 Webster]

   Chevalier d'industrie[F.], one who lives by persevering
      fraud; a pickpocket; a sharper.

   The Chevalier St. George (Eng. Hist.), James Francis Edward
      Stuart (son of James II.), called "The Pretender."

   The Young Chevalier, Charles Edward Stuart, son of the
      Chevalier St. George.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Chevalier
    n 1: French actor and cabaret singer (1888-1972) [syn:
         Chevalier, Maurice Chevalier]
    2: a gallant or courtly gentleman [syn: cavalier, chevalier]