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