A flat piece of wood or cork, strapped on the feet for walking over loose beach.

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1867.  in Smyth, Sailor’s Word-bk.

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1884.  H. Hewlett, in 19th Century, Aug., 329. Along the coast of Pevensey Bay one may meet peasants with flat pieces of wood called ‘backsters,’ fastened to the soles of their boots.

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