The Collaborative International Dictionary of English v.0.48:

Conclusion \Con*clu"sion\, n. [F., fr. L. conclusio. See
   Conclude.]
   1. The last part of anything; close; termination; end.
      [1913 Webster]

            A fluorish of trumpets announced the conclusion of
            the contest.                          --Prescott.
      [1913 Webster]

   2. Final decision; determination; result.
      [1913 Webster]

            And the conclusion is, she shall be thine. --Shak.
      [1913 Webster]

   3. Any inference or result of reasoning.
      [1913 Webster]

   4. (Logic) The inferred proposition of a syllogism; the
      necessary consequence of the conditions asserted in two
      related propositions called premises. See Syllogism.
      [1913 Webster]

            He granted him both the major and minor, but denied
            him the conclusion.                   --Addison.
      [1913 Webster]

   5. Drawing of inferences. [Poetic]
      [1913 Webster]

            Your wife Octavia, with her modest eyes
            And still conclusion.                 --Shak.
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   6. An experiment, or something from which a conclusion may be
      drawn. [Obs.]
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            We practice likewise all conclusions of grafting and
            inoculating.                          --Bacon.
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   7. (Law)
      (a) The end or close of a pleading, e.g., the formal
          ending of an indictment, "against the peace," etc.
      (b) An estoppel or bar by which a person is held to a
          particular position. --Wharton.
          [1913 Webster]

   Conclusion to the country (Law), the conclusion of a
      pleading by which a party "puts himself upon the country,"
      i.e., appeals to the verdict of a jury. --Mozley & W.

   In conclusion.
      (a) Finally.
      (b) In short.

   To try conclusions, to make a trial or an experiment.
      [1913 Webster]

            Like the famous ape,
            To try conclusions, in the basket creep. --Shak.

   Syn: Inference; deduction; result; consequence; end;
        decision. See Inference.
        [1913 Webster]

WordNet (r) 3.0 (2006):

conclusion
    n 1: a position or opinion or judgment reached after
         consideration; "a decision unfavorable to the opposition";
         "his conclusion took the evidence into account"; "satisfied
         with the panel's determination" [syn: decision,
         determination, conclusion]
    2: an intuitive assumption; "jump to a conclusion"
    3: the temporal end; the concluding time; "the stopping point of
       each round was signaled by a bell"; "the market was up at the
       finish"; "they were playing better at the close of the
       season" [syn: stopping point, finale, finis, finish,
       last, conclusion, close]
    4: event whose occurrence ends something; "his death marked the
       ending of an era"; "when these final episodes are broadcast
       it will be the finish of the show" [syn: ending,
       conclusion, finish] [ant: beginning]
    5: the proposition arrived at by logical reasoning (such as the
       proposition that must follow from the major and minor
       premises of a syllogism) [syn: conclusion, ratiocination]
    6: the act of ending something; "the termination of the
       agreement" [syn: termination, ending, conclusion]
    7: a final settlement; "the conclusion of a business deal"; "the
       conclusion of the peace treaty"
    8: the last section of a communication; "in conclusion I want to
       say..." [syn: conclusion, end, close, closing,
       ending]
    9: the act of making up your mind about something; "the burden
       of decision was his"; "he drew his conclusions quickly" [syn:
       decision, determination, conclusion]

Moby Thesaurus II by Grady Ward, 1.0:

233 Moby Thesaurus words for "conclusion":
   PS, Parthian shot, Z, accommodation, addendum, adjustment,
   affirmance, affirmation, aftermath, afterthought, allegation,
   announcement, annunciation, apodosis, appendix, arrangement,
   assertion, asseveration, assumption, attitude, averment,
   avouchment, avowal, back matter, bitter end, catastrophe, cease,
   ceasing, cessation, chorus, clear, climate of opinion, climax,
   close, closing, closure, coda, codicil, cogent, colophon,
   common belief, community sentiment, compelling, completing,
   completion, conceit, concept, conception, conclusive,
   consensus gentium, consequence, consequent, consideration,
   consummation, continuance, continuation, convincing, corollary,
   crack of doom, creed, culmination, curtain, curtains, death,
   decease, deciding, decisive, declaration, deduction, definitive,
   denouement, derivation, descendant, desistance, destination,
   destiny, determinant, determinate, determination, determinative,
   dictum, doom, double take, dying words, dynasty, effect, end,
   end point, end result, ending, enunciation, envoi, epilogue,
   eschatology, estimate, estimation, ethos, expiration, eye, fate,
   feeling, final result, final solution, final twitch, final words,
   finale, finality, finis, finish, finishing, follow-through,
   follow-up, full development, general belief, goal, heir, idea,
   illation, impression, incontrovertible, induction, inference,
   ipse dixit, irrefragable, irrefutable, izzard, judgment, last,
   last act, last breath, last gasp, last things, last trumpet,
   last words, latter end, lights, line, lineage, manifesto,
   maturation, maturity, mind, mystique, notion, observation,
   offspring, omega, opinion, parting shot, payoff, perfection,
   period, peroration, personal judgment, point of view,
   popular belief, position, position paper, positive declaration,
   posterity, postface, postfix, postlude, postscript, posture,
   precise, predicate, predication, presumption, prevailing belief,
   proclamation, profession, pronouncement, proposition, protest,
   protestation, public belief, public opinion, quietus,
   ratiocination, reaction, refrain, resolution, resting place,
   ripeness, rounding off, rounding out, say, say-so, saying, sealing,
   second thought, sentiment, sequel, sequela, sequelae, sequelant,
   sequent, sequitur, settlement, sight, signature, signing,
   solemnization, stance, stand, statement, stop, stoppage,
   stopping place, subscript, successor, suffix, supplement,
   swan song, tag, telling, term, terminal, termination, terminus,
   theory, thinking, thought, topping off, unambiguous, unanswerable,
   utterance, view, vouch, way of thinking, windup, word



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

CONCLUSION, practice. Making the last argument or address to the court or
jury. The party on whom the onus probandi is cast, in general has the
conclusion.



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

CONCLUSION, remedies. An estoppel; a bar; the act of a man by which he has
confessed a matter or thing which he can no longer deny; as, for example,
the sheriff is concluded by his return to a writ, and therefore, if upon a
capias he return cepi corpus, he cannot afterwards show that he did not
arrest the defendant, but is concluded by his return. Vide Plowd. 276, b; 3
Tho. Co. Litt. 600.