A musical instrument, supposed to have been a kind of lyre, or a harp with twelve strings. The Hebrew word nebhel, so rendered, is translated "viol" in Isaiah 5:12 (RSV, "lute"); 14:11. In Daniel 3:5,7,10,15, the word thus rendered is Chaldaic, pesanterin, which is supposed to be a word of Greek origin denoting an instrument of the harp kind.
These dictionary topics are from M.G. Easton M.A., D.D., Illustrated Bible Dictionary, Third Edition, published by Thomas Nelson, 1897. Public Domain, copy freely.
Easton, Matthew George. "Entry for 'Psaltery'". "Easton's Bible Dictionary".