Lexical Definition

‎πηγή‎ pēgḗ (pay-gay') flow ^G:N-F
probably from ‎πήγνυμι‎ (through the idea of gushing plumply)

fountain, well.

• a fount (literally or figuratively), i.e. source or supply (of water, blood, enjoyment) (not necessarily the original spring)

Abbott-Smith

πηγή, -ῆς, ἡ, [in LXX chiefly for עַיִן, also for מָקוֹר, etc.;]
a spring, fountain: Ja 3:11, II Pe 2:17; τ. ὑδάτων, Re 8:10 14:7 16:4; of a well fed by a spring, Jo 4:6; π. τοῦ αἵματος, of a flow of blood, Mk 5:29; metaph., Jo 4:14, Re 7:17 21:6.†

Abbott-Smith References

Liddell-Scott-Jones

πηγή,

Doric dialect πᾱγά, ἡ, running water, used by [Refs 8th c.BC+] always in plural, streams, πηγαὶ ποταμῶν [Refs 8th c.BC+]

__2 metaphorically, of tears, πηγαὶ κλαυμάτων, δακρύων, streams.., [Refs 5th c.BC+]; also πηγαὶ γάλακτος, βοτρύων, [Refs 5th c.BC+]; πόντου πηγαῖς with sea-water, [Refs]; πηγαὶ τροφῆς τῷ γεννωμένῳ, of mother's milk, [Refs 5th c.BC+]
__II fount, source, τοῦ Νείλου [Refs 5th c.BC+]; πηγαὶ ἡλίου the fount of light, i. e. the South, [Refs 4th c.BC+]; πηγαὶ νυκτός the North, [Refs 5th c.BC+]; πυρὸς παγαί[Refs 5th c.BC+]; πηγὴ ἀργύρου, of the silver-mines at Laureion, [Refs 4th c.BC+]; τῆς ἀκουούσης π. δι᾽ ὤτων, i.e. the sense of hearing, [Refs 5th c.BC+]; ἀπὸ μιᾶς ἀρχῆς καὶ π. [Refs 4th c.BC+]
__II.2 metaphorically, source, origin, mostly in singular, κακῶν π. [Refs 4th c.BC+]; αἱ τέχναι, ἃς πηγάς φασι τῶν καλῶν εἶναι [Refs 5th c.BC+]; π. ἡδονῶν, τοῦ φρονεῖν, νοσημάτων, etc., [Refs 5th c.BC+]; βέβηκα π. εἰς ἐμάς I have returned to the source of my existence, [Refs 5th c.AD+]
__II.3 inner canthus of eye, supposed source of tears, [Refs 2nd c.AD+]