pervert

debase, vitiate, deprave, corrupt, debauch, pervert mean to cause deterioration or lowering in quality or character.

debase implies a loss of position, worth, value, or dignity.

vitiate implies a destruction of purity, validity, or effectiveness by allowing entrance of a fault or defect.

deprave implies moral deterioration by evil thoughts or influences.

corrupt implies loss of soundness, purity, or integrity.

debauch implies a debasing through sensual indulgence.

pervert implies a twisting or distorting from what is natural or normal.