Usage: 3 forms in 4 verses
Form Translated As     In Verse(s)
συμβουλίασ advice LXX.Prov.12.15
my advice LXX.2Chr.25.16
συμβουλίαν with advice LXX.1Kgs.1.12
συμβουλίαι my advice LXX.Ps.119.24

Liddell-Scott-Jones

συμβουλία (sumboulia) advice G:N-F

συμβουλία-ία,

Ionic dialect -ιη, , advice or counsel given, especially in public affairs, [Refs 5th c.BC+]; Περιάνδρου Θρασυβούλῳ σ. [Refs 4th c.BC+]; advice of an oracle, τοῦ Ἀπόλλωνος σ. [Refs 2nd c.BC+]: plural, counsels, [Refs 5th c.BC+]

__II counsel, consultation, λαβεῖν τινα εἰς σ. [Refs 4th c.BC+]
__III prescription, recipe for a charm, [Refs 1st c.AD+]