Vitiation

n.

1.

The act of vitiating, or the state of being vitiated; depravation; corruption; invalidation; as, the vitiation of the blood; the vitiation of a contract. The vitiation that breeds evil acts. - G. Eliot.

Noun

1.

vitiation - nullification by the destruction of the legal force; rendering null; "the vitiation of the contract"

invalidate, nullification, override, vitiate, void