emperor

Etymology

From Middle English emperour, borrowed from Anglo-Norman emperour and Old French empereor (Modern French empereur), from Latin imperātor (“emperor; commander”), from imperāre (“to command”). Doublet of imperator.

noun

1. The male monarch or ruler of an empire.
   They asked Julius Caesar, the valiant Roman emperor, what was the best death. He answered, that which is unexpected, which comes suddenly and unforeseen 1885, John Ormsby, transl., Don Quixote, Miguel de Cervantes, Volume 2 Chapter XXIV
2. 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, Het Spinhuis, Transactions: Essays in Honor of Jeremy F. Boissevain
   After his death in 683 she ruled for seven years as regent and then, deposing her son, became emperor herself, the only woman in Chinese history to hold the title. 2002, The Heritage of World Civilizations: To 1700, page 226
   Empress, imperial regent, and even emperor herself (r. 797–802), Irene was an important and powerful figure at the Byzantine court in the late eighth and early ninth century. 2008, Encyclopedia of Barbarian Europe: Society in Transformation, page 211
   Originally the wife of the emperor, she engineered the imperial succession so that she could serve first as regent to a boy emperor and then as emperor herself. 2013, Voyages in World History, page 213
   Where is Sindbad? I have a summons for him direct from the galactic emperor herself. He is to be brought here immediately to give an explanation for his recent actions. 2016, Commander Pakydus, Sindbad & the 7 Galaxies
3. (political theory) Specifically, the ruler of the Holy Roman Empire; the world-monarch.
   The Investiture Controversy was a conflict between the Emperor and the Pope.
4. (tarot) The fourth trump or major arcana card of the tarot deck.
5. A large, relatively valuable marble in children's games.
   But marbles are not only used to play games: they are also traded. In this market, the value of the different kinds of marbles (oilies, emperors, etc.) is determined by local supply and demand and not by the price of the marbles […] 2001, Paul Webley, The economic psychology of everyday life, page 39
6. Any fish of the family Lethrinidae.
7. (entomology) Any of various butterflies of the subfamily Charaxinae.
8. (entomology) Any of various large dragonflies of the cosmopolitan genus Anax.
9. An emperor penguin.
   We do not know if the emperors are monogamous. I know some of the penguins species mate for life. 2008, Gloria Clifford, Emperor Penguins: The Lords of Antarctica
   During pairing, mates walk an average of only 90 m per day, and, while incubating, male emperors move an average of 30 m per day. 2012, Lloyd S. Davis, John T. Darby, Penguin Biology, page 273
   If they were emperors, I wanted a better view. Being told they were emperors was no good; I needed to see them. But as quickly as we had spotted them, they spotted us. Sliding on their bellies, two emperors began to rush over. 2019, Lindsay McCrae, My Penguin Year: Living with the Emperors