The Collaborative International Dictionary of English v.0.48:

Jockey \Jock"ey\, v. t. [imp. & p. p. Jockeyed; p. pr. & vb.
   n. Jockeying.]
   1. " To jostle by riding against one." --Johnson.
      [1913 Webster]

   2. To play the jockey toward; to cheat; to trick; to impose
      upon in trade; as, to jockey a customer.
      [1913 Webster]

   3. To maneuver; to move in an intricate manner so as to avoid
      obstacles; as, to jockey a large cabinet up a winding
      staircase.
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Jockey \Jock"ey\, v. i.
   1. To play or act the jockey; to cheat.
      [1913 Webster]

   2. To maneuver oneself aggressivley or skillfully so as to
      achieve an advantage; as, he jockeyed himself into
      position to be noticed.
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Jockey \Jock"ey\, n.; pl. Jockeys. [Dim. of Jack, Scot. Jock;
   orig., a boy who rides horses. See 2d Jack.]
   [1913 Webster]
   1. A professional rider of horses in races. --Addison.
      [1913 Webster]

   2. A dealer in horses; a horse trader. --Macaulay.
      [1913 Webster]

   3. A cheat; one given to sharp practice in trade.
      [1913 Webster]

WordNet (r) 3.0 (2006):

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"
    v 1: defeat someone through trickery or deceit [syn: cheat,
         chouse, shaft, screw, chicane, jockey]
    2: compete (for an advantage or a position)
    3: ride a racehorse as a professional jockey