A plant or animal that establishes itself in an area where it previously did not exist.
A non-native person who comes to a country from another country to permanently settle there.
Of or relating to immigrants or the act of immigrating.
A plant introduced in a place outside its native range but is not persistently naturalized.
A person (especially a child) who is homeless and without means of support; also, a person excluded from society; an outcast.
A very thin person.
Something found, especially if without an owner; something which comes along, as it were, by chance.
A small flag used as a signal.
Something (such as clouds or smoke) carried aloft by the wind.
To cast aside or reject, and thus make a waif.