treasonable

from WordNet (r) 3.0 (2006)

treasonable
    adj 1: having the character of, or characteristic of, a traitor;
           "the faithless Benedict Arnold"; "a lying traitorous
           insurrectionist" [syn: {faithless}, {traitorous},
           {unfaithful}, {treasonable}, {treasonous}]

from The Collaborative International Dictionary of English v.0.48

Treasonable \Trea"son*a*ble\, a.
   Pertaining to treason; consisting of treason; involving the
   crime of treason, or partaking of its guilt.
   [1913 Webster]

         Most men's heads had been intoxicated with imaginations
         of plots and treasonable practices.      --Clarendon.
   [1913 Webster]

   Syn: Treacherous; traitorous; perfidious; insidious.
        [1913 Webster] --{Trea"son*a*ble*ness}, n. --
        {Trea"son*a*bly}, adv.
        [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

37 Moby Thesaurus words for "treasonable":
      Judas-like, Trojan-horse, apostate, betraying, breakaway,
      collaborative, degenerate, disloyal, double-crossing, extreme,
      extremistic, factious, faithless, fifth-column, insurgent,
      insurrectionary, mutineering, mutinous, quisling, quislingistic,
      rebel, rebellious, recreant, renegade, revolutional, revolutionary,
      riotous, seditionary, seditious, subversive, tergiversant,
      tergiversating, traitorous, treasonous, turbulent, turncoat,
      two-timing

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