The most common and most likely answer to this crossword clue is the 9 letter word IMMIGRANT
I've seen this crossword clue in The Daily Telegraph
I
M
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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 IMMIGRANT mean?
IMMIGRANT noun- A non-native person who comes to a country from another country in order to permanently settle there.
- A plant or animal that establishes itself in an area where it previously did not exist.
- Of or relating to immigrants or the act of immigrating.