Selah
The name Selah means “the end; a pause”.
Easton's Bible Dictionary 1897
Smith's Bible Dictionary 1863
This word, which is found only in the poetical books of the Old Testament, occurs seventy-one times in the Psalms and three times in Habakkuk. It is probably a term which had a meaning in the musical nomenclature of the Hebrews, though what that meaning may have been is now a matter of pure conjecture. (Gesenius and Ewald and others think it has much the same meaning as our interlude,--a pause in the voices singing, while the instruments perform alone.)
International Standard Bible Encyclopedia 1915
se'-la.
See MUSIC, II, 1.