The most common and most likely answer to this crossword clue is the 9 letter word BRIMSTONE
I've seen this crossword clue in The Times
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More clues leading to the result BRIMSTONE
- Butterfly is absolutely filled with colour
- Nearly run over brownish-grey butterfly
- Butterfly is full colour
- Butterfly practically overflows with colour
- Disturbing sermon with bit concerning one of hell’s torments
- Border’s attitude? It’s something fiery
- Steamed with fire
- Sulphur once providing lips with hue
- One of 18 having weight on the borderline
- Butterfly fluttering on timbers
Buddy explains!

The straight part
We know that "butterfly" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case butterfly = brimstone.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 BRIMSTONE mean?
BRIMSTONE noun- The sulfur of Hell; Hell, damnation.
- Sulfur.
- A whore.
- Used attributively as an intensifier in exclamations.
- The butterfly Gonepteryx rhamni of the Pieridae family.