An immigrant who has entered a country (often as a migrant worker) and has no documentation authorizing them to (still) be present there.

(countable, offensive) Someone who has immigrated into a country by bypassing customs and immigration controls.

plural of economic immigrant

An economic migrant.

plural of landed immigrant

(politics) Opposing immigration.

The migration of people across national borders in a way that violates the immigration laws of the destined country.

plural of illegal immigration