U+133E3 Egyptian Hieroglyph Y008

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A sistrum (plural: sistra or (in Latin) sīstra; from the Greek σεῖστρον seistron of the same meaning; literally "that which is being shaken", from σείειν seiein, "to shake") is a musical instrument of the percussion family, a form of rattle, used most notably by the ancient Egyptians. It consists of a handle and a U-shaped metal frame, made of brass or bronze and ranging from 30 to 76 cm (12–30 in) in width. The frame supports sliding metal cross-bars, which may hold metal rings. When shaken, the small rings or loops of thin metal on its movable crossbars produce a sound that can vary from a soft clank to a loud jangling. Its name in the ancient Egyptian language was sekhem (sḫm) or sesheshet (sššt) because of the sound it made when it rattled. The ancient Egyptian sistrum had important associations with religious and ritualistic practices concerning various musical and joyful deities.

A sekhem is the simpler, hoop-like sistrum, while sesheshet (an onomatopoeic word) is the naos-shaped one.

The English language has adopted the name sistrum to refer to modern-day West-African disc-rattle instruments.