in the game of chess, means placing your adversary's king in such a position that he can neither cover nor move out of check. Figuratively, “to checkmate” means to foil or outwit another; checkmated, outmanoeuvred. “Mate” (Arabic, mat, dead; Spanish, matar, to kill). The German schach means both chess and check, and the Italian scacco means the squares of the chess-board; but schach-matt and scaccomatto = check-mate. The French échec is a “stoppage,” whence donner or faire échec et mat, to make a stoppage
(check) and dead; the Spanish, xaque de mate means the check of death (or final check).
If we go to Arabic for “mate,” why not go there for “check” also? And “sheik mat” = the king dead, would be consistent and exact. (See Chess)
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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