Psalm - Vine's Expository Dictionary of New Testament Words
Psalm
[ 1,,G5568, psalmos ]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," Luke 20:42; Luke 24:44; Acts 1:20;
(b) of a particlular "psalm," Acts 13:33 (cp. Acts 13:35);
(c) of "psalms" in general, 1 Corinthians 14:26; Ephesians 5:19; Colossians 3:16.
Note: For psallo, rendered "let him sing psalms" in James 5:13, See MELODY, SING.