The Collaborative International Dictionary of English v.0.48:

Disaccordant \Dis`ac*cord"ant\, a.
   Not accordant. --Fabyan.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

126 Moby Thesaurus words for "disaccordant":
   adversary, adversative, adverse, alien, antagonistic, anti,
   antipathetic, antithetic, assorted, at cross-purposes,
   at loggerheads, at odds, at variance, at war, chill, chilly,
   clashing, cold, colliding, competitive, con, conflicting,
   contradictory, contrary, contrasted, contrasting, cool, counter,
   cranky, cross, departing, deviating, deviative, different,
   differentiated, differing, disagreeable, disagreeing, discordant,
   discrepant, discrete, discriminated, disharmonious, disjoined,
   disparate, disproportionate, dissentient, dissident, dissimilar,
   dissonant, distinct, distinguished, divergent, diverging, divers,
   diverse, diversified, enemy, fractious, frosty, grating,
   heterogeneous, hostile, icy, immiscible, in disagreement,
   inaccordant, incompatible, incongruous, inconsistent, inconsonant,
   inharmonious, inhospitable, inimical, irreconcilable, jangling,
   jarring, many, motley, multifarious, negative, noncooperative,
   obstinate, opponent, opposed, opposing, opposite, oppositional,
   oppositive, oppugnant, out of accord, out of whack, overthwart,
   perverse, poles apart, poles asunder, recalcitrant, refractory,
   repugnant, rival, separate, separated, several, strained, tense,
   unamiable, unamicable, unconformable, uncongenial, uncooperative,
   uncordial, unequal, unfavorable, unfriendly, ungenial,
   unharmonious, unlike, unpropitious, unsociable, variant, varied,
   variegated, various, varying, widely apart, worlds apart