The most common and most likely answer to this crossword clue is the 6 letter word LEAVER
I've seen this crossword clue in Independent
L
E
A
V
E
R
More clues leading to the result LEAVER
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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 LEAVER mean?
LEAVER noun- (UK politics) Someone who supports Brexit, the United Kingdom's exit from the European Union.
- One who leaves.