(n.) Distinction by contrast.

antagonism antipathy antithesis clashing collision con conflict confrontation contradiction contraindication contraposition contrariety contrast counterposition cross-purposes demarcation differentiation disagreement discrepancy distinction distinctiveness distinguishment division hairsplitting hostility inconsistency inimicalness microscopic distinction nice distinction nuance oppositeness opposition opposure oppugnance oppugnancy perversity polarity repugnance segregation separation shade of difference showdown subtle distinction trichoschistism