noun

emperor

EM-per-er/ˈempərər/

A supreme ruler, especially a male ruler of an empire.

The emperor rules a vast empire from his capital.

A mature East Asian emperor seated formally on a dignified throne with plain historical robes and attendants, no caricature.

Etymology

An emperor was literally a commander. The Roman title honored a successful general before becoming a title of supreme rulers, connecting military command with rule over an empire.

In context

Rotten Tomatoes TV14:23

in a world that has been turned over into the evil Galactic Empire. So everywhere he looks he sees the hand of the Emperor.

Sam Witwer & Dave Filoni on Becoming 'Star Wars: Maul -- Shadow Lord'

More examples

The emperor appoints governors to oversee distant provinces.
Our class studies the emperors of ancient Rome.
The old coin bears a portrait of the emperor.

Forms

emperor · emperors

empress noun — A female sovereign or an emperor’s wife.

imperial adjective — Relating to an emperor or an empire.

Similar words

monarch: Any royal sovereign, not specifically the ruler of an empire.
sovereign: Emphasizes supreme authority rather than a particular royal title.
king: A male ruler of a kingdom rather than an empire.