Contraindication

(n.) An indication or symptom which forbids the method of treatment usual in such cases.

Thesaurus Entries

antagonism, antipathy, antithesis, clashing, collision, conflict, confrontation, contradiction, contradistinction, contraposition, contrariety, contrast, counterposition, cross-purposes, disagreement, discrepancy, hostility, inconsistency, inimicalness, oppositeness, opposition, opposure, oppugnance, oppugnancy, perversity, polarity, repugnance, showdown