Neutral:
* Non-native: Emphasizes the lack of native status.
* Immigrant: Focuses on the act of coming to a new country.
* Alien: A formal, legal term, can sometimes sound negative.
* Visitor: Emphasizes temporary stay.
* Expatriate: Someone living outside their native country, often for work.
* International: Broad term, emphasizing global connection.
Informal:
* Foreigner: Common, but can be perceived as outdated or even offensive.
* Outsider: Can be neutral or negative, depending on context.
* Stranger: Emphasizes unfamiliarity.
More specific:
* Tourist: Someone visiting for pleasure.
* Refugee: Someone fleeing their home country due to danger.
* Guest worker: Someone working in a country they are not a citizen of.
It's important to be mindful of the potential connotations of each word. For example, "foreigner" can be seen as outdated and potentially offensive, while "alien" has negative connotations in some contexts.
The best choice will depend on the specific situation.