intransigent

from WordNet (r) 3.0 (2006)

intransigent
    adj 1: impervious to pleas, persuasion, requests, reason; "he is
           adamant in his refusal to change his mind"; "Cynthia was
           inexorable; she would have none of him"- W.Churchill; "an
           intransigent conservative opposed to every liberal
           tendency" [syn: {adamant}, {adamantine}, {inexorable},
           {intransigent}]

from The Collaborative International Dictionary of English v.0.48

Intransigent \In*trans"i*gent\, a. [F. intransigeant (cf. Sp.
   intransigente); pref. in- not + L. transigere to come to an
   agreement; trans across + agere to lead, act.]
   Refusing compromise; uncompromising; inflexible;
   irreconcilable. --Lond. Sat. Rev.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

74 Moby Thesaurus words for "intransigent":
      adamant, adamantine, ass, bigot, bitter-ender, brawler, bullethead,
      cast-iron, defendant, diehard, disputant, dissentient, dissident,
      dogmatist, donkey, dour, fanatic, firm, flinty, grim, hard,
      hard-core, hardnose, immovable, immutable, implacable, impliable,
      inelastic, inexorable, inflexible, intransigeant, iron,
      irreconcilable, last-ditcher, litigant, maverick, mule, naysayer,
      negativist, noncooperator, objector, obstructionist, obstructive,
      opposer, oppositionist, perverse fool, pighead, plaintiff,
      positivist, protester, purist, quarreler, relentless, resister,
      rigid, rigorous, rock-ribbed, scrapper, standpat, standpatter,
      steely, stern, stickler, stiff, unaffected, unalterable, unbending,
      unchangeable, uncompromising, ungiving, unmoved, unrelenting,
      unyielding, wrangler