Lexical Definition

‎φέγγος‎ phéngos (feng'-gos) brightness ^G:N-N
probably akin to the base of ‎φῶς‎ (compare ‎φθέγγομαι‎)

light.

• brilliancy

Abbott-Smith

φέγγος, -ους, τό [in LXX chiefly for נֹגַהּ ;]
light, brightness, usually c. gen. of something that shines or reflects: of the moon, Mt 24:29, Mk 13:24; of a lamp, Lk 11:33 (WH, RV, φῶς).†
SYN.: αὐγή, q.v.

Abbott-Smith References

Liddell-Scott-Jones

φέγγος, εος, τό,

light, splendour, lustre, τῆλε δὲ φ. ἀπὸ χροὸς ἀθανάτοιο λάμπε θεᾶς [LXX+4th c.BC+]; φ. ἀστραπῆς ὅπλων[LXX]: frequently like{φάος}, of daylight, either absolutely or with some word added, φ. ἡλίου [Refs 5th c.BC+]; without the Article, φ. εἰσορᾶν θεοῦ [Refs 5th c.BC+]; ὦ φέγγος[Refs 5th c.BC+]

__b moonlight, [Refs 5th c.BC+]; νυκτερινὰ φέγγη, opposed to ἡμερινὸν φῶς, [φέγγος σελήνης 5th c.AD(?): Hesychius Legal icographus ">Refs 5th c.BC+] see at {φέγγο; τὸ φ. [τοῦ γάλακτος}], of the milky way, [Refs 4th c.BC+]
__c of men, φ. ἰδεῖν, προσιδεῖν, to see the light, come into the world, ἐπεὶ πάμπρωτον εἶδον φ. [Refs 5th c.BC+]
__d day, τριταῖον ἤδη φ. [Refs 5th c.BC+]; μοιρίδιον φ. ={μ. ἦμαρ}, [Refs 5th c.BC+]
__2 the light of torches or fire, φ. λαμπάδων [Refs 4th c.BC+]; πυρός[Refs]: a light, torch, [Refs 5th c.BC+]; plural φέγγη torches or watch-fires, [Refs 4th c.BC+]
__3 the light of the eyes, φ. ὀμμάτων [Refs 5th c.BC+]; τυφλὸν φ, i.e. blindness, [Refs 5th c.BC+]
__II light, as a metaphorically for delight, glory, pride, joy, [Refs 5th c.BC+]; of persons, [Refs 5th c.BC+]; φ. ὀπώρας, of wine, [Refs]
__II.2 lustre, δικαιοσύνης καὶ σωφροσύνης [LXX+5th c.BC+]

_{LSJ Scripture Refs: LXX.Ezek.10.4 ☩ LXX.Hab.3.11}