emperor

noun10

1. •
   a man who rules a very large area made up of many nations

   • In imperial China, it was often a responsibility of the emperor to evaluate his predecessor after the latter's death.
2. •
   The title of an emperor.

   • As military attaché to the British Embassy in Berlin he enjoyed the esteem of Emperors William and Frederick. — 1902
3. •
   Any monarch ruling an empire, irrespective of gender, with "empress" contrasting to mean the consort of an emperor.

   • In 690 Wu usurped the throne and became Emperor herself, which proved a unique event in the history of China. — 1994
4. •
   Specifically, the ruler of the Holy Roman Empire; the world-monarch.

   • The Investiture Controversy was a conflict between the Emperor and the Pope.
5. •
   An emperor penguin (Aptenodytes forsteri).

   • We do not know if the emperors are monogamous. I know some of the penguins species mate for life. — 2008
6. •
   Any of various butterflies of the subfamily Charaxinae.
7. •
   The fourth trump or major arcana card of the tarot deck.
8. •
   Any of various large dragonflies of the cosmopolitan genus Anax.
9. •
   A large, relatively valuable marble in children's games.
10. •
    Any fish of the family Lethrinidae.