1. a substance or agent used to make something black or darker
2. a person who damages someone’s reputation or character
Usage: figurative

Examples

• She used a shoe blackener to restore the color of her leather boots.
• The blackener worked well on the old metal fence.
• He applied the blackener evenly across the surface.
• The politician accused his opponent of being a reputation blackener.
• Don’t be a blackener of other people’s good names.
• The blackener left dark stains on her hands.