The most common and most likely answer to this crossword clue is the 10 letter word UNSOCIABLE
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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 UNSOCIABLE mean?
UNSOCIABLE noun- A person who is not sociable.
- Not desiring the company of others
- Not congenial or compatible
- Unfriendly