Compare concepts: colony and colonial empire.

A colony is a specific territory that is under the rule of an imperial state.

A colonial empire is a state that rules over many colonies. That is, we can say that the colony is one of the components of the colonial empire. The very essence of such empires is that they develop thanks to the resources of their colonies. That is, they can be called parasites that existed at the expense of other states. The largest empire of this type was England.