1. (n.) An assertion contrary to what has already been said or affirmed\; denial of the truth of a statement or assertion; contrary declaration; gainsaying.

2. (n.) Direct opposition or repugnancy; inconsistency; incongruity or contrariety; one who, or that which, is inconsistent.

abjuration abjurement abrogation absolute contradiction annulment answer antagonism antipathy antithesis argumentation backlash bucking challenge chucking chucking out clashing collision complete answer conflict confounding confrontation confutation contempt contention contradistinction contraindication contraposition contrariety contrary assertion contrast contravention contraversion controversion controversy counteraction countering counterposition counterworking crankiness cross-purposes crosscurrent crossing crotchetiness declination declining demolition denial despisal despising difference disaccord disaccordance disaffirmation disagreement disallowance disapproval disavowal discard disclaimer disclamation discord discordance discordancy discounting discrediting discrepancy disharmony dismissal disownment disparity disproof disregard dissension dissent dissidence dissonance disunion disunity divergence diversity effective rejoinder exception exclusion faction forswearing friction gainsaying head wind hostility ignoring impugnation impugnment inaccordance inconsistency inequality inimicalness interference jarring kick negation nonacceptance nonapproval nonconformity nonconsideration nullification opposing oppositeness opposition opposure oppugnance oppugnancy oppugnation overthrow overthrowal passing by perverseness perversity polarity putting away putting out reaction rebuff rebutment rebuttal recalcitrance recantation recoil refusal refutal refutation rejection renitency renouncement renunciation repercussion repudiation repugnance repulse resistance retractation retraction revocation revolt scouting showdown spurning squelch standing against subversion swimming upstream throwing out traversal turning out undercurrent undermining unharmoniousness upset upsetting variance