(to cause something) to become black

darken

to make (something) dirty, impure or diseased (by touching or adding something impure)

adulterate

to make (a region, water; a person's thoughts etc) dirty or impure

corrupt, violate

to use (a sacred thing or place) in an unworthy or wicked way

abuse, violate

to make (air, rivers etc) dirty, impure

make dirty; corrupt

dullness (on metal) because the brightness has gone; to lessen the quality of (a person's reputation)

dirty, corrupt