Blemish

To mark with deformity; to injure or impair, as anything which is well formed, or excellent; to mar, or make defective, either the body or mind.

To tarnish, as reputation or character; to defame.

Any mark of deformity or injury, whether physical or moral; anything that diminishes beauty, or renders imperfect that which is otherwise well formed; that which impairs reputation.

a mark or flaw that spoils the appearance of something (especially on a person's body); "a facial blemish"