Source : Webster's Revised Unabridged Dictionary (1913)

Deprave \De*prave"\, n. 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.]

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

   2. To make bad or worse; to vitiate; to corrupt.

            Whose pride depraves each other better part.
                                                  --Spenser.

   Syn: To corrupt; vitiate; contaminate; pollute.

Source : WordNet®

depraved
     adj 1: having the nature of vice [syn: {evil}, {vicious}]
     2: hopelessly bad; "an unregenerate criminal" [syn: {unreformable},
         {unregenerate}]
     3: marked by immorality; deviating from what is considered
        right or proper or good; "depraved criminals"; "a
        perverted sense of loyalty"; "the reprobate conduct of a
        gambling aristocrat" [syn: {immoral}, {perverse}, {perverted},
         {reprobate}]