Usage: 5 forms in 20 verses
Form Translated As     In Verse(s)
ψαλτηρίων of your psalteries LXX.Ezek.26.13
ψαλτηρίω a psaltery LXX.Ps.49.4LXX.Ps.150.3
psaltery LXX.Ps.33.2LXX.Ps.92.3LXX.Ps.144.9LXX.Ps.149.3
ψαλτηρίου psaltery LXX.Isa.5.12LXX.Isa.38.20LXX.Ezek.33.32LXX.Dan.3.5LXX.Dan.3.7LXX.Dan.3.10LXX.Dan.3.15
ψαλτήριον O psaltery LXX.Ps.57.8
psaltery LXX.Gen.4.21LXX.Job.21.12LXX.Ps.81.2LXX.Ps.108.2
ψαλτήρια psalteries LXX.Neh.12.27

Liddell-Scott-Jones

ψαλτήριον (psaltērion) a psaltery G:N-N

ψαλτήριον-τήριον, τό,

stringed instrument, psaltery, harp, τρίγωνα ψ. [LXX+4th c.BC+]

LSJ Scripture Refs: LXX.Gen.4.21