The most common and most likely answer to this crossword clue is the 2 plus 2 letter word NO GO
N
O
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More clues leading to the result NO GO
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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.
Crossword Answer definitions
NO GO noun- (with indefinite article) Something which should not or cannot be done.
- Not functioning properly.
- Of a place, not to be entered.