1.Of or pertaining to an empire, or to an emperor; as, an imperial government; imperial authority or edict. "The last That wore the imperial diadem of Rome."
2.Belonging to, or suitable to, supreme authority, or one who wields it; royal; sovereign; supreme. "The imperial democracy of Athens." "Who, as Ulysses says, opinion crowns With an imperial voice." "To tame the proud, the fetter'd slave to free, These are imperial arts, and worthy thee." "He sounds his imperial clarion along the whole line of battle."
3.Of superior or unusual size or excellence; as, imperial paper; imperial tea, etc.