IMPERIUM
imperium
(noun) supreme authority; absolute dominion
empire, imperium
(noun) the domain ruled by an emperor or empress; the region over which imperial dominion is exercised
Source: WordNet® 3.1
Etymology
Noun
imperium (countable and uncountable, plural imperia or imperiums)
Supreme power; dominion.
The right to command the force of the state; sovereignty.
Source: Wiktionary
Im*pe"ri*um, n.; pl. Imperia (#). [L. See Empire.]
1. Supreme power; absolute dominion; empire.
2. (Law) The right to command, which includes the right to employ
the force of the state to enforce the laws. It is one of the
principal attributes of the executive power.
Source: Webster’s Unabridged Dictionary 1913 Edition