Plural of chessboard, the square-patterned board used for playing chess, with 64 alternating light and dark squares.
From chess (the game, from Old French eschecs, ultimately from Persian shah meaning 'king') + board (from Old English bord); literally the board for chess.
The chessboard's 64-square pattern actually comes from an ancient Indian legend about a mathematician who asked for grains of rice in doubling amounts per square—the math would have buried the kingdom in rice.
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