deprave

v. t. [ imp. & p. p. Depraved p. pr. & vb. n. Depraving. ] [ L. depravare, depravatum; de- + pravus crooked, distorted, perverse, wicked. ] 1. To speak ill of; to depreciate; to malign; to revile. [ Obs. ] [ 1913 Webster ]

And thou knowest, conscience, I came not to chide
Nor deprave thy person with a proud heart. Piers Plowman. [ 1913 Webster ]

2. To make bad or worse; to vitiate; to corrupt. [ 1913 Webster ]

Whose pride depraves each other better part. Spenser.

Syn. -- To corrupt; vitiate; contaminate; pollute. [ 1913 Webster ]