The most common and most likely answer to this crossword clue is the 6 letter word INKING
I've seen this crossword clue in The Guardian
I
N
K
I
N
G
More clues leading to the result INKING
Buddy explains!
The straight part
We know that "Blackening/Blackening" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case blackening/blackening = inking.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does INKING mean?
INKING verb- To apply ink to; to cover or smear with ink.
- To sign (a contract or similar document).
- To apply a tattoo to (someone).
- (of a squid or octopus) to eject ink (sense 3)
- An application of ink.
- Work done by an inker, one kind of commercial artist
- Inputting text or drawings into a computer, tablet, or similar apparatus using a stylus.
- A defensive activity where ink is released by squids, cuttlefish, etc.