The sovereign or supreme monarch of an empire; a title of dignity superior to that of king; as, the emperor of Germany or of Austria; the emperor or Czar of Russia.
(Science: zoology) emperor goose, a large, strong British butterfly (Apatura iris).
Origin: OF. Empereor, empereour, f. Empereur, L. Imperator, fr. Imperare to command; in in _ parare to prepare, order. See parade, and cf. Imperative, empress.