A dash-board.

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1856.  He looked with a dubious expression at the broken dasher, swinging forward and back at every motion.—Sara Robinson, ‘Kansas,’ p. 173 (1857).

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1858.  

        Thoroughbrace bison-skin, thick and wide;
Boot, top, dasher, from tough old hide
Found in the pit when the tanner died.
O. W. Holmes, ‘The One-Hoss Shay.’ (N.E.D.)    

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