Vitiate

I found this fine word in the interesting and well-written book Not in Our Classrooms, edited by Eugenie C. Scott and Glenn Branch. You might notice that this is first verb that I've used for word of the day so far.

Vitiate (vish-ee-eyt) [Latin vitiÄre; to spoil.]

v.

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.

Usage: The sigificance for creationist claims about irreducible complexity is clear: the possibility of change of function in evolution vitiates the argument.

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