The most common and most likely answer to this crossword clue is the 4 plus 1 plus 3 letter word BUST A GUT
I've seen this crossword clue in Financial Times
B
U
S
T
A
G
U
T
More clues leading to the result BUST A GUT
- Give it everything reversing one vessel towards another
- American chasing game however claims to work hard
- Try very hard as upper class male — however kept outside
- Coach, before game with United: ‘Time to go all out‘
- Labour intensively to include American label in bar
- Make a huge effort getting university blokes’ party into bar
- 9 Make every effort in one area to separate two others that may 26
- Try very hard to pull replacement player over, collecting cheers!
- Try very hard except being occupied by 6 and university
- Try very hard to meet qualification for intestinal surgery?
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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.