Source : Webster's Revised Unabridged Dictionary (1913)

Jockey \Jock"ey\, n.; pl. {Jockeys}. [Dim. of Jack, Scot. Jock;
   orig., a boy who rides horses. See 2d {Jack}.]
   1. A professional rider of horses in races. --Addison.

   2. A dealer in horses; a horse trader. --Macaulay.

   3. A cheat; one given to sharp practice in trade.

Jockey \Jock"ey\, v. t. [imp. & p. p. {Jockeyed}; p. pr. & vb.
   n. {Jockeying}.]
   1. `` To jostle by riding against one.'' --Johnson.

   2. To play the jockey toward; to cheat; to trick; to impose
      upon in trade; as, to jockey a customer.

Jockey \Jock"ey\, v. i.
   To play or act the jockey; to cheat.

Source : WordNet®

jockey
     n 1: someone employed to ride horses in horse races
     2: an operator of some vehicle or machine or apparatus; "he's a
        truck jockey"; "a computer jockey"; "a disc jockey"

jockey
     v 1: defeat someone in an expectation through trickery or deceit
          [syn: {cheat}, {chouse}, {shaft}, {screw}, {chicane}]
     2: compete (for an advantage or a position)
     3: ride a race-horse as a professional jockey