XXkas-ta-nets, kas-ta-nets (mena`an`im): Are mentioned in 2 Sam 6:5 among the musical instruments upon which David and the house of Israel played at the time of the bringing up of the ark out of the house of Abinadab. This word is incorrectly translated "cornets" in the King James Version. The castanet was probably about the same kind of instrument as the Egyptian sistrum, and the Revised Version (British and American) has "sistra" in the margin of 2 Sam 6:5. The sialrum was a loop-shaped metal frame through which were passed loose rods at the ends of which were rings. The instrument was held by a long handle and was rattled during songs and dances. It was used in Egypt in religious worship or to scare away evil influences. There is only the one reference to this instrument in the Bible.
A. W. Fortune