WordNet (r) 3.0 (2006):

pluralistic
    adj 1: of or relating to the philosophical doctrine of
           pluralism; "a pluralistic culture"

Moby Thesaurus II by Grady Ward, 1.0:

125 Moby Thesaurus words for "pluralistic":
   absolute, amalgamated, ambiguous, ambivalent, amphibious,
   aristocratic, authoritarian, autocratic, autonomous, blended,
   bureaucratic, capricious, certain, changeable, changing, choppy,
   civic, civil, combined, complex, composite, compound, compounded,
   conglomerate, constitutional, dappled, democratic, despotic,
   deviating, deviative, deviatory, dictatorial, different,
   disorderly, divaricate, divergent, diversified, diversiform,
   eclectic, equivocal, erose, erratic, fascist, federal, federalist,
   federalistic, fifty-fifty, governmental, gubernatorial,
   half-and-half, heterogeneous, heteronomous, impulsive,
   inconsistent, inconstant, indiscriminate, intricate, ironic,
   irregular, jagged, jerky, jumbled, many-sided, matriarchal,
   matriarchic, medley, mercurial, mingled, miscellaneous, mixed,
   monarchal, monarchial, monarchic, monocratic, more, more than one,
   motley, multifaceted, multinational, multiracial, mutable,
   nonconformist, nonstandard, nonuniform, not singular, numerous,
   official, oligarchal, oligarchic, parliamentarian, parliamentary,
   patchy, patriarchal, patriarchic, plural, plurative, political,
   promiscuous, ragged, republican, rough, scrambled, self-governing,
   some, spasmodic, sporadic, syncretic, theocratic, thrown together,
   totalitarian, unequable, unequal, uneven, unorthodox, unstable,
   unsteady, unsystematic, ununiform, variable, varied, variegated,
   variform, various, varying, wavering