Empire
Part of speech: noun
Definition: A political unit having an extensive territory or comprising a number of territories or nations and ruled by a single supreme authority. A group of states or other territories that owe allegiance to a foreign power. A state ruled by an emperor. Any vast area under the power of one person; most commonly used in business, e.g. "the McDonalds empire".
Example sentence: To plunder, to slaughter, to steal, these things they misname empire; and where they make a wilderness, they call it peace.
Imperium
Part of speech: noun
Definition: Supreme power; dominion.The right to command the force of the state, sovereignty.