Legal Definitions - alien friend

Definition: An alien friend is an alien who is a citizen or subject of a friendly power.

Example: A person from Canada who is living in the United States and has not yet become a citizen is considered an alien friend.

This example illustrates that an alien friend is someone who is not a citizen of the country they are residing in, but is from a friendly country. In this case, the person is from Canada, which is considered a friendly power to the United States.