To debase
pervert, vitiate, degrade, bribe, suborn, adulterate, depreciate, deprave, debauch, defile, demoralize, pollute, taint, contaminate, infect, stain, spoil, ruin, alloy, bastardize, blight, blemish, mark against, undermine, subvert, impair, mar, injure, harm, hurt, damage, deface, disfigure, deform, abuse, mistreat, misuse, dishonor, disgrace, despoil, violate, demean, lower, pull down, reduce, weaken, abase, poison, warp, mislead, misguide, cause to degenerate, cause to deteriorate; see also bribe.
Antonyms purify, clean*, restore.