blacken

American  

[blak-uhn] / ˈblæk ən /

verb (used with object)

1. to make black; darken.

2. to speak evil of; defame.

   to blacken a person's reputation.

   Synonyms:

   calumniate, traduce, libel, slander, smear, denigrate

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verb (used without object)

1. to grow or become black.

blacken British  

/ ˈblækən /

verb

1. to make or become black or dirty

2. (tr) to defame; slander (esp in the phrase blacken someone's name )

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Other Word Forms

• blackener noun

Etymology

Origin of blacken

Middle English word dating back to 1250–1300; black, -en ¹

Example Sentences

A new scientific review suggests that Polygonum multiflorum, a root used in traditional Chinese medicine for more than a thousand years to "blacken hair and nourish essence," could be a promising alternative for managing AGA.

From Science Daily • Feb. 9, 2026

These incidents may temporarily blacken the eyes of the NBA and Major League Baseball but sports gambling is here to stay.

From The Wall Street Journal • Dec. 5, 2025

But as the ghostly figure draws nearer, its skin rots and its eyes blacken.

From New York Times • Mar. 31, 2023

Sarit and Itamar opted to leave the onion on the grill to blacken thoroughly — but only on the surface.

From Salon • Dec. 2, 2021

I had callused my hands; I had scratched dirt to blacken the nails, which I cut straight across to make stubby fingers.

From "The Woman Warrior" by Maxine Hong Kingston

Related Words

• blot
• smudge
• stain
• sully
• tarnish