IMPE'RIAL, a. [L.imperialis, from impero, to command. See Emperor.]

1. Pertaining to an empire, or to an emperor; as an imperial government; an imperial diadem; imperial authority or edict; imperial power or sway.

2. Royal; belonging to a monarch; as an imperial palace; imperial arts.

3. Pertaining to royalty; denoting sovereignty.

4. Commanding; maintaining supremacy; as the imperial democracy of Athens.

Imperial chamber, the sovereign court of the German empire.

Imperial city, a city in Germany which has no head but the emperor.

Imperial diet,an assembly of all the states of the German empire.