The most common and most likely answer to this crossword clue is the 8 letter word EMIGRANT
I've seen this crossword clue in The Times
E
M
I
G
R
A
N
T
More clues leading to the result EMIGRANT
- Old lady broaching issue is a Leaver
- One settling elsewhere - German, it turned out
- Put out about old woman, one moving abroad
- Settler perhaps restraining road rage
- Music company once given sum of money for expat
- Refugee possibly in English plane encountering tirade
- Wild tiger and man, one on the 22 across
- One leaving country with Russian fighter fled into Egypt
- Issue about elderly relative being someone in altered state
- Grandma having been captured by the enemy uprising, one leaves the country
Buddy explains!

The straight part
We know that "one moving abroad" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one moving abroad = emigrant.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 EMIGRANT mean?
EMIGRANT noun- Someone who leaves a country to settle in a new country.
- Any of various pierid butterflies of the genus Catopsilia. Also called a migrant.