The Collaborative International Dictionary of English v.0.48:

Ungodly \Un*god"ly\, a.
   1. Not godly; not having regard for God; disobedient to God;
      wicked; impious; sinful.
      [1913 Webster]

   2. Polluted by sin or wickedness.
      [1913 Webster]

            The hours of this ungodly day.        --Shak.
      [1913 Webster]
      [1913 Webster] -- Un*god"li*ly, adv. --
      Un*god"li*ness, n.
      [1913 Webster]
      [1913 Webster]

WordNet (r) 3.0 (2006):

ungodly
    adj 1: characterized by iniquity; wicked because it is believed
           to be a sin; "iniquitous deeds"; "he said it was sinful
           to wear lipstick"; "ungodly acts" [syn: iniquitous,
           sinful, ungodly]

Moby Thesaurus II by Grady Ward, 1.0:

121 Moby Thesaurus words for "ungodly":
   Adamic, a bit thick, a bit thin, absurd, appalling, atheistic,
   awful, backsliding, bad, barbarous, beastly, beyond belief,
   blasphemous, carnal, corrupt, cursed, damnable, demoniac,
   demoniacal, demonic, depraved, devilish, diabolic, diabolical,
   doubtable, doubtful, dreadful, dubious, dubitable, erring, evil,
   execrable, fallen, fiendish, flagitious, fleshly, frail, frightful,
   ghoulish, godless, hard of belief, hard to believe, heinous,
   hellish, heretical, iconoclastic, immoral, impious, implausible,
   improper, impure, inconceivable, incredible, indecent, indelicate,
   infernal, infirm, iniquitous, irreligious, irreverent, lapsed,
   malodorous, monstrous, nasty, not deserving belief, of easy virtue,
   open to doubt, open to suspicion, outrageous, passing belief,
   peccable, postlapsarian, preposterous, problematic, prodigal,
   profane, questionable, recidivist, recidivistic, ridiculous, rough,
   sacrilegious, satanic, shocking, sinful, staggering belief,
   suspect, suspicious, tall, terrible, thick, thin, un-Christly,
   unangelic, unbecoming, unbelievable, unchaste, unchristian,
   uncivilized, unclean, unconscionable, unconvincing, undecorous,
   unearthly, ungood, unhallowed, unholy, unimaginable, unrighteous,
   unsaintly, unthinkable, untoward, unvirtuous, unworthy of belief,
   vile, villainous, virtueless, wanton, wayward, weak, wicked