A more thorough explanation:

Definition: A foreigner is someone who is not a citizen or inhabitant of a particular country or city.

Examples:

• An American visiting Japan is considered a foreigner.
• A person from France living in the United States is a foreigner.
• A tourist from Canada visiting Mexico is a foreigner.

The examples illustrate that a foreigner is someone who is not a citizen or inhabitant of a particular country or city. In each example, the person is from a different country than the one they are visiting or living in, making them a foreigner.