Source : Webster's Revised Unabridged Dictionary (1913)

Four-in-hand \Four"-in-hand\, a.
   Consisting of four horses controlled by one person; as, a
   four-in-hand team; drawn by four horses driven by one person;
   as, a four-in-hand coach. -- n. A team of four horses driven
   by one person; also, a vehicle drawn by such a team.

         As quaint a four-in-hand As you shall see. --Tennyson.

Source : WordNet®

four-in-hand
     n 1: a long necktie that is tied in a slipknot with one end
          hanging in front of the other
     2: a carriage pulled by four horses with one driver [syn: {coach},
         {coach-and-four}]