The most common and most likely answer to this crossword clue is the 10 letter word EXPATRIATE
I've seen this crossword clue in The Times
E
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The straight part
We know that "one in exile?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one in exile? = expatriate.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 EXPATRIATE mean?
EXPATRIATE noun- One who lives outside their own country.
- To banish; to drive or force (a person) from his own country; to make an exile of.
- To withdraw from one’s native country.
- To renounce the rights and liabilities of citizenship where one is born and become a citizen of another country.
- Living outside of one's own country.