debase

corrupt morally or by intemperance or sensuality; "debauch the young people with wine and women"; "Socrates was accused of corrupting young men"; "Do school counselors subvert young children?"; "corrupt the morals"

lower in value by increasing the base-metal content

corrupt, debase, or make impure by adding a foreign or inferior substance; often by replacing valuable ingredients with inferior ones; "adulterate liquor"