The most common and most likely answer to this crossword clue is the 9 letter word COMMUNITY
C
O
M
M
U
N
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Y
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The straight part
We know that "Nation" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case nation = community.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 COMMUNITY mean?
COMMUNITY noun- A group sharing a common understanding, and often the same language, law, manners, and/or tradition.
- A residential or religious collective; a commune.
- A group of interdependent organisms inhabiting the same region and interacting with each other.
- A group of people interacting by electronic means for educational, professional, social, or other purposes; a virtual community.
- The condition of having certain attitudes and interests in common.
- Common enjoyment or possession; participation.
- Common character; likeness.
- Commonness; frequency.