A colony is a group of people who settle in a new place but keep ties to their homeland. The people who founded the United States first came to America to live as part of a British colony.
Colony comes from the Latin colonia, meaning "settled land, farm." Colony can also mean "a group of people who've gathered to live near each other and share the same interest." An artists' colony would be a place where everyone's an artist, while a Dunkin' Donuts colony would be full of coffee lovers. The same rules apply to the animal kingdom — an ant colony has a shared interest in ruining your picnic.