A colonia was a Roman outpost, usually established by veterans of a Roman Legion, who received land as a part of their retirement from the Legions. In time the term evolved to denote the highest status of a Roman city.
Some examples would be
Colonia also refers to a low-income community, often comprised of seasonal and/or migrant workers, generally found within 150 miles of the US-Mexico border.
Geography of the Roman Empire | Roman towns types | Roman colonies