adjective
Definition: In a situation where a king in a game of chess cannot escape being captured, resulting in a loss; also used to describe a situation where someone faces an unavoidable defeat or loss.
Example: After a series of poor moves, he found himself in a checkmated position, unable to make any legal moves.
verb
Definition: To have put an opponent in a position in chess where they cannot escape defeat, resulting in the end of the game.
Example: The player checkmated his opponent in just twenty moves.