From the site:

Word History: The words check, chess, and shah are all related. Shah, as one might think, is a borrowing into English of the Persian title for the monarch of that country. The Persian word shāh was also a term used in chess, a game played in Persia long before it was introduced to Europe. One said shāh as a warning when the opponent’s king was under attack. The Persian word in this sense, after passing through Arabic, probably Old Spanish, and then Old French, came into Middle English as chek about seven hundred years ago. Chess itself comes from a plural form of the Old French word that gave us the word check. Checkmate, the next stage after check, goes back to the Arabic phrase shāh māt, meaning “the king is dead.” Through a complex development having to do with senses that evolved from the notion of checking the king, check came to mean something used to ensure accuracy or authenticity. One such means was a counterfoil, a part of a check, for example, retained by the issuer as documentation of a transaction. Check first meant “counterfoil” and then came to mean anything, such as a bill or bank draft, with a counterfoil—or eventually even without one.

…and I wonder… is Obama going to checkmate Clinton in the race to become the Democrat’s candidate? This year is just full of surprises.