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]

The Collaborative International Dictionary of English v.0.48:

Adventure \Ad*ven"ture\, v. t. [imp. & p. p. Adventured; p.
   pr. & vb. n. Adventuring.] [OE. aventuren, auntren, F.
   aventurer, fr. aventure. See Adventure, n.]
   1. To risk, or hazard; jeopard; to venture.
      [1913 Webster]

            He would not adventure himself into the theater.
                                                  --Acts xix.
                                                  31.
      [1913 Webster]

   2. To venture upon; to run the risk of; to dare.
      [1913 Webster]

            Yet they adventured to go back.       --Bunyan,
      [1913 Webster]

            Discriminations might be adventured.  --J. Taylor.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Adventure \Ad*ven"ture\, v. i.
   To try the chance; to take the risk.
   [1913 Webster]

         I would adventure for such merchandise.  --Shak.
   [1913 Webster]

WordNet (r) 3.0 (2006):

adventure
    n 1: a wild and exciting undertaking (not necessarily lawful)
         [syn: adventure, escapade, risky venture, dangerous
         undertaking]
    v 1: take a risk in the hope of a favorable outcome; "When you
         buy these stocks you are gambling" [syn: gamble,
         chance, risk, hazard, take chances, adventure,
         run a risk, take a chance]
    2: put at risk; "I will stake my good reputation for this" [syn:
       venture, hazard, adventure, stake, jeopardize]

Moby Thesaurus II by Grady Ward, 1.0:

137 Moby Thesaurus words for "adventure":
   Clio, accomplished fact, accomplishment, achievement, act, acta,
   action, adventures, affair, annals, aristeia, autobiography, bet,
   biographical sketch, biography, blow, bold stroke, case history,
   casualty, chance, chance hit, chronicle, chronicles, chronology,
   circumstance, confessions, contingency, contingent, coup,
   curriculum vitae, danger, dare, dealings, deed, diary, doing,
   doings, effort, emprise, endanger, endeavor, enterprise, episode,
   escapade, event, expedition, experience, experiences, exploit,
   exploration, fact, fait accompli, feat, fluke, fortuity, fortunes,
   freak accident, gamble, gest, go, hagiography, hagiology, hand,
   handiwork, hap, happening, happenstance, hazard, heroic act,
   historiography, history, imperil, incident, jeopardize, job,
   journal, legend, life, life and letters, life story, long odds,
   long shot, lucky shot, maneuver, martyrology, matter of fact,
   measure, memoir, memoirs, memorabilia, memorial, memorials,
   mission, move, necrology, obituary, occasion, occurrence,
   operation, overt act, particular, passage, performance, peril,
   phenomenon, photobiography, pilgrimage, proceeding, production,
   profile, punt, quest, reality, record, res gestae, resume, risk,
   speculation, stake, step, story, stroke, stunt, theory of history,
   thing, thing done, threaten, tour de force, transaction, turn,
   turn of events, undertaking, venture, wager, waver, work, works



Bouvier's Law Dictionary, Revised 6th Ed (1856):

ADVENTURE, bill of. A writing signed by a merchant, to testify that the
goods shipped on board a certain vessel are at the venture of another
person, he himself being answerable only for the produce. Techn. Dict.



Bouvier's Law Dictionary, Revised 6th Ed (1856):

ADVENTURE, crim. law. See Misadventure.



Bouvier's Law Dictionary, Revised 6th Ed (1856):

ADVENTURE, mer. law. Goods sent abroad under the care of a supercargo, to be
disposed of to the best advantage for the benefit of his employers, is
called an adventure.