The Collaborative International Dictionary of English v.0.48:

Damnation \Dam*na"tion\, n. [F. damnation, L. damnatio, fr.
   damnare. See Damn.]
   1. The state of being damned; condemnation; openly expressed
      disapprobation.
      [1913 Webster]

   2. (Theol.) Condemnation to everlasting punishment in the
      future state, or the punishment itself.
      [1913 Webster]

            How can ye escape the damnation of hell? --Matt.
                                                  xxiii. 33.
      [1913 Webster]

            Wickedness is sin, and sin is damnation. --Shak.
      [1913 Webster]

   3. A sin deserving of everlasting punishment. [R.]
      [1913 Webster]

            The deep damnation of his taking-off. --Shak.
      [1913 Webster]

WordNet (r) 3.0 (2006):

damnation
    n 1: the act of damning
    2: the state of being condemned to eternal punishment in Hell
       [syn: damnation, eternal damnation]

Moby Thesaurus II by Grady Ward, 1.0:

76 Moby Thesaurus words for "damnation":
   anathema, anathematizing, arraignment, ban, blame, blasphemy,
   bloodbath, blue ruin, breakup, carnage, castigation, censure,
   commination, condemnation, consumption, conviction, curse,
   death sentence, death warrant, decimation, decrial, denouncement,
   denunciation, depredation, desolation, despoilment, despoliation,
   destruction, devastation, disintegration, disorganization,
   disruption, dissolution, doom, evil eye, excommunication,
   excoriation, execration, flaying, fulmination, fustigation,
   guilty verdict, havoc, hecatomb, hex, holocaust, impeachment,
   imprecation, indictment, judgment, malison, malocchio, perdition,
   pillorying, proscription, rap, ravage, reprehension, reprobation,
   ruin, ruination, sentence, shambles, skinning alive, slaughter,
   spoliation, stricture, thundering, undoing, vandalism,
   verdict of guilty, waste, whammy, wrack, wrack and ruin, wreck



Easton's 1897 Bible Dictionary:

Damnation
   in Rom. 13:2, means "condemnation," which comes on those who
   withstand God's ordinance of magistracy. This sentence of
   condemnation comes not from the magistrate, but from God, whose
   authority is thus resisted.

     In 1 Cor. 11:29 (R.V., "judgment") this word means
   condemnation, in the sense of exposure to severe temporal
   judgements from God, as the following verse explains.

     In Rom. 14:23 the word "damned" means "condemned" by one's own
   conscience, as well as by the Word of God. The apostle shows
   here that many things which are lawful are not expedient; and
   that in using our Christian liberty the question should not
   simply be, Is this course I follow lawful? but also, Can I
   follow it without doing injury to the spiritual interests of a
   brother in Christ? He that "doubteth", i.e., is not clear in his
   conscience as to "meats", will violate his conscience "if he
   eat," and in eating is condemned; and thus one ought not so to
   use his liberty as to lead one who is "weak" to bring upon
   himself this condemnation.