checkmate
1. [ noun ] complete victory
Related terms: victory chess
2. [ verb ] (chess) place an opponent's king under an attack from which it cannot escape and thus ending the game; in a game of chess
Synonyms: mate
Examples:

"Kasparov checkmated his opponent after only a few moves"

Related terms: beat chess
3. [ noun ] (chess,games) a chess move constituting an inescapable and indefensible attack on the opponent's king
Synonyms: mate
Related terms: chess_move
Similar spelling:   chiasmatic