The most common and most likely answer to this crossword clue is the 10 letter word DISTORTION
I've seen this crossword clue in Financial Times
D
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More clues leading to the result DISTORTION
Buddy explains!
The straight part
We know that "colouring" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case colouring = distortion.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 DISTORTION mean?
DISTORTION noun- An act of distorting.
- A result of distorting.
- A misrepresentation of the truth.
- Noise or other artifacts caused in the electronic reproduction of sound or music.
- An effect used in music, most commonly on guitars in rock or metal.
- (optics) an aberration that causes magnification to change over the field of view.