1. to make faulty or defective; to impair the quality or effectiveness of something
Usage: formal
2. to make legally invalid or ineffective
Usage: legal

Examples

• The contamination vitiates the entire water supply.
• His bias vitiates the credibility of his research.
• A single error vitiates the whole argument.
• The fraud vitiates the contract completely.
• Poor methodology vitiates the study’s conclusions.
• The judge ruled that the procedural error vitiates the verdict.
• Excessive heat vitiates the effectiveness of the medicine.