- to impair the quality of; make faulty; spoil.
- to impair or weaken the effectiveness of.
- to debase; corrupt; pervert.
- to make legally defective or invalid; invalidate
1534, from L. vitiatus, pp. of vitiare "tomake faulty, injure, spoil, corrupt," fromvitium "fault, defect, blemish, crime,vice" (http://dictionary.reference.com/browse/vitiate)
"On March 5 the legislature voted its 'adhesion to the new government.'
"Other official elements in the state vitiated this resolution, however. Several federal police corps of northern Maderista origins would not accept the new regime."
- John Womack, Zapata and the Mexican Revolution