The Collaborative International Dictionary of English v.0.48:

D'enouement \D['e]`noue`ment"\, n. [F. d['e]nouement, fr.
   d['e]nouer to untie; pref. d['e]- (L. dis-) + nouer to tie,
   fr. L. nodus knot, perh. for gnodus and akin to E. knot.]
   1. The unraveling or discovery of a plot; the catastrophe,
      especially of a drama or a romance.
      [1913 Webster]

   2. The solution of a mystery; issue; outcome.
      [1913 Webster]

WordNet (r) 3.0 (2006):

denouement
    n 1: the outcome of a complex sequence of events
    2: the final resolution of the main complication of a literary
       or dramatic work

Moby Thesaurus II by Grady Ward, 1.0:

140 Moby Thesaurus words for "denouement":
   Z, accomplishment, action, anagnorisis, angle, answer, apodosis,
   architectonics, architecture, argument, ascertainment, atmosphere,
   background, bitter end, catastrophe, ceasing, cessation,
   characterization, clearing up, climax, coda, color, completion,
   complication, conclusion, consummation, continuity, contrivance,
   crack of doom, cracking, culmination, curtain, curtains, death,
   decease, decipherment, decoding, design, destination, destiny,
   determination, development, device, disentanglement, doom, effect,
   end, end point, end result, ending, envoi, epilogue, episode,
   eschatology, expiration, explanation, fable, falling action, fate,
   final result, final solution, final twitch, final words, finale,
   finality, finding, finding-out, finis, finish, gimmick, goal,
   incident, interpretation, issue, izzard, last, last act,
   last breath, last gasp, last things, last trumpet, last words,
   latter end, line, local color, mood, motif, movement, mythos,
   omega, outcome, payoff, period, peripeteia, peroration, plan, plot,
   quietus, reason, recognition, resolution, resolving, resting place,
   result, riddling, rising action, scheme, secondary plot, slant,
   solution, solving, sorting out, stoppage, stopping place, story,
   structure, subject, subplot, swan song, switch, term, terminal,
   termination, terminus, thematic development, theme, tone, topic,
   twist, unraveling, unriddling, unscrambling, unspinning,
   untangling, untwisting, unweaving, upshot, windup, working,
   working-out