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overseas
adv.
Beyond the sea; abroad.
adj.
Of, relating to, originating in, or situated in countries across the sea.
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abroad
adv. & adj.
1. Out of one's own country.
2. In a foreign country or countries.
3. Away from one's home.
4. In circulation; at large.
5. Covering a large area; widely: “An epidemic is abroad in America” (Richard M. Smith).
6. Not on target; in error.
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So not a lot of difference really