vitiate [vish-ee-eyt]
verb (used with object), vi·ti·at·ed, vi·ti·at·ing.
1. to impair the quality of; make faulty; spoil.
2. to impair or weaken the effectiveness of.
3. to debase; corrupt; pervert.
4. to make legally defective or invalid; invalidate: to vitiate a claim.
Can be confused
ameliorate, obviate
See more synonyms on Thesaurus.com
Origin: 1525–35; < Latin vitiātus, past participle of vitiāre to spoil, derivative of vitium blemish, vice + -ātus -ate
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