also: おうしゃ
noun
Refers to a sovereign or ruler; compared with 王 or 国王, 王者 often sounds somewhat elevated, literary, or descriptive rather than like an everyday title.
古代の王者は大きな権力を持っていた。
Ancient rulers held great power.
noun
Common in sports, games, competitions, and figurative uses for the person or team at the top; often appears in phrases such as 世界王者 and 王者決定戦.
彼は三年連続で世界王者になった。
He became world champion for the third year in a row.
王者らしい落ち着いた試合運びだった。
It was the calm handling of a match that you would expect from a champion.