The most common and most likely answer to this crossword clue is the 5 letter word SHTUP
I've seen this crossword clue in Financial Times
S
H
T
U
P
More clues leading to the result SHTUP
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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 SHTUP mean?
SHTUP verb- To push.
- To have sex (with).