The Collaborative International Dictionary of English v.0.48:

Trojan \Tro"jan\, a. [L. Trojanus, fr. Troja, Troia, Troy, from
   Tros, Gr. Trw`s, Trwo`s, Tros, the mythical founder of Troy.]
   1. Of or pertaining to ancient Troy or its inhabitants. -- n.
      A native or inhabitant of Troy.
      [1913 Webster]

   2. One who shows the pluck, endurance, determined energy,
      strength, or the like, attributed to the defenders of
      Troy; -- used chiefly or only in the phrase

   like a Trojan; as, he endured the pain like a Trojan; he
      studies like a Trojan.
      [Webster 1913 Suppl.]

            Tim jumped like a Trojan from the bed. --Finnegan's
                                                  Wake (Irish
                                                  song)
      [PJC]