A percussion instrument (idiophone) consisting of a pair of concave shells joined on one edge by a string, held in the hand and used to produce clicking sounds.(noun)
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Use "castanets" in a sentence
"Daikoku band: they were to sing the ballads Those with the castanets were the Ebisu party and formed the chorus."
"Other girls were provided with a kind of castanets, -- two flat pieces of hard dark wood, connected by a string."
""Mexican Girl" brings in some obvious yet suitable flourishes, such as castanets and Spanish guitar, neither of which one tends to associate with the Beach Boys."