primarily denoted "a striking or twitching with the fingers (on musical strings);" then, "a sacred song, sung to musical accompaniment, a psalm." It is used (a) of the OT book of "Psalms," Luk 20:42, Luk 24:44, Act 1:20; (b) of a particlular "psalm," Act 13:33 (cp. Act 13:35); (c) of "psalms" in general, 1Co 14:26, Eph 5:19, Col 3:16.
Note: For psallo, rendered "let him sing psalms" in Jam 5:13, see MELODY, SING.