The origin of the name of the game of chess is uncertain. It most probably came from the Arabic word for king, “Shah”, which then passed into Old French as eschec, then into Middle English as chek. This gave rise to the chess term "check" signifying that the king is under attack. In the 18th century it also came to mean “identifying token”, giving us the word “cheque”. The Old French plural of eschec was esches, borrowed into Middle English as ches.
The word “checkmate” is used in chess to signify that the opponent’s king is under attack (“in check”), that the king cannot move anywhere without remaining under attack and that the attacking piece is unable to be taken by the opponent. This results in the loss of the game. Most etymologists are of the opinion that the word :checkmate” comes from the Arabic “Shah mat”, meaning “the king is dead”, although some maintain that the more correct translation is “the king is helpless”. Other etymologists are of the opinion that it comes not from Arabic but from the Persian “shaah maat”, meaning that the king is powerless, stymied, defeated.