1. (n.) A placing over against, in opposite position; an antithesis\.

2. (n.) A so-called immediate inference which consists in denying the original subject of the contradictory predicate; e.g.: Every S is P; therefore, no Not-P is S.

antagonism antipathy antithesis backlash bucking challenge clashing collision con conflict confrontation confutation contention contradiction contradistinction contraindication contrariety contrast contravention contraversion counteraction counterposition counterworking crankiness cross-purposes crosscurrent crossing crotchetiness denial disagreement discrepancy dissent friction head wind hostility impugnation impugnment inconsistency inimicalness interference kick negation nonconformity opposing oppositeness opposition opposure oppugnance oppugnancy oppugnation perverseness perversity polarity reaction rebutment rebuttal recalcitrance recoil refusal rejection renitency repercussion repugnance resistance revolt showdown standing against swimming upstream traversal undercurrent