vitiate

The least admixture of a lie, -- for example, the taint of vanity, the least attempt to make a good impression, a favorable appearance, -- will instantly vitiate the effect.

Dissolute and vitiated alike, they confided in, and ever acted in mutual concert with each other's plans, according to the deep subtleties of their reasonings, which linked them together by some secret spell.

‘Crush the cockatrice,’ he groaned, from his death-cell. ‘I am dead in law’ – but of the girl he denied that he had ‘attempted to vitiate her at Nine years old’; for ‘upon the word of a dying man, both her Eyes did see, and her Hands did act in all that was done’.

[…]all the hinges of the animal frame are subverted, every animal function is vitiated; the carcass retains but just life enough to make it capable of suffering.