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n. A percussion instrument consisting of a pair of slightly concave shells of ivory or hardwood, held in the palm of the hand by a connecting cord over the thumb and clapped together with the fingers. Often used in the plural.

n. A single handheld percussion instrument, from of a pair of concave shells joined on one edge by string. Normally not used in singular.

n. See castanets.

n. One of a pair of slightly concave spoon-shaped shells of ivory or hard wood, loosely fastened together at the base, and used (slung over the thumb) in beating time to music or dancing.

"A little to one side sit old men musicians, who keep up a kind of castanet rattle with split willow wands and a droning accompaniment of meaningless syllables, like the burden of old ballads."

castanets   

castanetist   

cithern    tambourine    mill-wheel    psaltery    kettledrum