Definitions

1. noun

A person who has a great deal of power and influence in a particular sphere of activity, typically within a business or government, often through unscrupulous means.

“The billionaire’s rise to power was seen as a prime example of oligarchic influence in the country.”

2. noun

A member of the upper class in ancient Greece, especially one of the few hundred richest and most powerful citizens of Athens.

“The ancient city was ruled by a council of oligarchs who made decisions for the benefit of their own class.”