4. vitiate to make legally invalid; invalidate: to vitiate a claim.
Etymology: (1525–35; < L vitiātus, ptp. of vitiāre to spoil, der. of vitium blemish, vice1)
Definition of 'vitiate'
Princeton's WordNet
1. (verb)corrupt, pervert, subvert, demoralize, demoralise, debauch, debase, profane, vitiate, deprave, misdirect corrupt morally or by intemperance or sensuality "debauch the young people with wine and women"; "Socrates was accused of corrupting young men"; "Do school counselors subvert young children?"; "corrupt the morals"
3. (verb)invalidate, void, vitiate take away the legal force of or render ineffective "invalidate a contract"
Definition of 'vitiate'
Webster Dictionary
1. (verb)vitiate to make vicious, faulty, or imperfect; to render defective; to injure the substance or qualities of; to impair; to contaminate; to spoil; as, exaggeration vitiates a style of writing; sewer gas vitiates the air
2. (verb)vitiate to cause to fail of effect, either wholly or in part; to make void; to destroy, as the validity or bindingforce of an instrument or transaction; to annul; as, any undue influence exerted on a jury vitiates their verdict; fraud vitiates a contract
Definitions of vitiate 
