The Collaborative International Dictionary of English v.0.48:

Adventure \Ad*ven"ture\ (?; 135), n. [OE. aventure, aunter,
   anter, F. aventure, fr. LL. adventura, fr. L. advenire,
   adventum, to arrive, which in the Romance languages took the
   sense of "to happen, befall." See Advene.]
   [1913 Webster]
   1. That which happens without design; chance; hazard; hap;
      hence, chance of danger or loss.
      [1913 Webster]

            Nay, a far less good to man it will be found, if she
            must, at all adventures, be fastened upon him
            individually.                         --Milton.
      [1913 Webster]

   2. Risk; danger; peril. [Obs.]
      [1913 Webster]

            He was in great adventure of his life. --Berners.
      [1913 Webster]

   3. The encountering of risks; hazardous and striking
      enterprise; a bold undertaking, in which hazards are to be
      encountered, and the issue is staked upon unforeseen
      events; a daring feat.
      [1913 Webster]

            He loved excitement and adventure.    --Macaulay.
      [1913 Webster]

   4. A remarkable occurrence; a striking event; a stirring
      incident; as, the adventures of one's life. --Bacon.
      [1913 Webster]

   5. A mercantile or speculative enterprise of hazard; a
      venture; a shipment by a merchant on his own account.
      [1913 Webster]

   A bill of adventure (Com.), a writing setting forth that
      the goods shipped are at the owner's risk.
      [1913 Webster]

   Syn: Undertaking; enterprise; venture; event.
        [1913 Webster]