Lexical Definition

‎ἐνέργεια‎ enérgeia (en-erg'-i-ah) active energy ^G:N-F
from ‎ἐνεργής‎

operation, strong, (effectual) working.

• efficiency ("energy")

Abbott-Smith

** ἐνέργεια, -ας, ἡ (< ἐνεργής), [in LXX: Wi 7:17, 26 13:4 18:22, II Mac 3:29, III Mac 4:21 5:12, 28 * ;]
operative power (as distinct from δύναμις, potential power), working: of God, Eph 1:19 3:7 4:16, Phl 3:21, Col 1:29 2:12; of Satan, II Th 2:9, 11 (cf. M, Th., l.c.; AR, Eph., 241 ff.; Cremer, 261).†

Abbott-Smith References

Liddell-Scott-Jones

ἐνέργεια-εια, ἡ,

activity, operation, opposed to ἕξις (disposition), [Refs 4th c.BC+]; opposed to ἀογία, [Refs 2nd c.AD+]; physiological function, [Refs 2nd c.AD+]; performance, τῶν καθηκόντων [Refs 1st c.AD+]; activity, of drugs, [Refs 2nd c.AD+]; force, of an engine, [Refs 1st c.BC+] (but, mechanism, 'action', [Refs 2nd c.BC+]

__b workmanship, Aristeas [Refs]
__2 especially of divine or supernatural action, [NT+3rd c.AD+]; magical operation, ἱερὰ ἐ. [Refs]
__3 plural, ἐνέργειαειαι cosmic forces, [Refs 2nd c.AD+]
__4 Grammars, active force, opposed to πάθος, [Refs 2nd c.BC+]; ἐνέργειαειαι καὶ πάθη active and passive forms, [Refs 2nd c.AD+]
__5 Rhet., vigour of style, [Refs 4th c.BC+]
__II in the philosophical of [Refs 4th c.BC+] actuality, Metaphorical[Refs]; opposed to ὕλη, [Refs]; ἡ ὡς ἐ. οὐσία, substance in the sense of actuality, [Refs]; opposed to ἐντελέχεια, as actuality to full reality, [Refs]; ἐνεργείᾳ actually, opposed to δυνάμει, [Refs]

_{LSJ Scripture Refs: Eph.1.19}