in·con·sist·ent / ˌinkənˈsistənt/ • adj. not staying the same throughout; having self-contradictory elements: police interpretation of the law was often inconsistent. ∎ acting at variance with one's own principles or former conduct: parents can become inconsistent and lacking in control over their children. ∎ (inconsistent with) not compatible or in keeping with: he had done nothing inconsistent with his morality. ∎ erratic in behavior or action: we're too inconsistent to win the league. DERIVATIVES: in·con·sist·ent·ly adv.
Reciprocally contradictory or repugnant.
Things are said to be inconsistent when they are contrary to each other to the extent that one implies the negation of the other. For example, a city ordinance might be inconsistent with a state statute; or two defenses to a crime, such as the defenses of alibi and self-defense, are inconsistent.