Heb. shophar, "brightness," with reference to the clearness of its sound (1 Chr. 15:28; 2 Chr. 15:14; Ps. 98:6; Hos. 5:8). It is usually rendered in the Authorized Version "trumpet." It denotes the long and straight horn, about eighteen inches long. The words of Joel, "Blow the trumpet," literally, "Sound the cornet," refer to the festival which was the preparation for the day of Atonement. In Dan. 3:5, 7, 10, 15, the word (keren) so rendered is a curved horn. The word "cornet" in 2 Sam. 6:5 (Heb. mena'an'im, occurring only here) was some kind of instrument played by being shaken like the Egyptian sistrum, consisting of rings or bells hung loosely on iron rods.
Easton's Bible Dictionary. M.G. Easton. 1897.