Verb blacken has 2 senses
- blacken, melanize, melanise, nigrify, black - make or become black; "The smoke blackened the ceiling"; "The ceiling blackened"
--1 is one way to discolor, discolour, colour, color
Antonyms:  whiten, white
Sample sentences:
 Something ----s
 Somebody ----s something
 Something ----s something
 - char, blacken, scorch - burn slightly and superficially so as to affect color; "The cook blackened the chicken breast"; "The fire charred the ceiling above the mantelpiece"; "the flames scorched the ceiling"
--2 is one way to burn
Sample sentences:
 Somebody ----s something
 Something ----s something
 
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