The most common and most likely answer to this crossword clue is the 3 letter word COR
C
O
R
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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 COR mean?
COR interjection- Expression of surprise.
- Various former units of volume, particularly: