Improve

Antonyms of IMPROVE

diminish, spoil, corrupt, pollute, damage, drop, blight, halt, dirty, descend, recede, repress, demote, retrogress, tarnish, lessen, weaken, retreat, hurt, deteriorate, lose, reduce, vitiate, aggravate, injure, harm, hinder, blemish, blow, decrease, stop, worsen, mar, dull, ruin, lower, decline, depress, debase, flaw, impair, destroy.