Quick Definition
ἀεί Adv always
Strong's Definition
from an obsolete primary noun (apparently meaning continued duration); "ever,"by qualification regularly; by implication, earnestly; --always, ever.
UBS Dictionary of the Greek New Testament
advb. | ἀΐδιος
67.86 · Time · Duration of Time without Reference to Points or Units of Time: Time, Spend Time, Always, Eternal, Old, Immediately, Young
always, constantly, continually duration of time, either continuous or episodic, but without limits In some languages there may be problems involved in rendering ἀεί or διὰ παντός[b], since there may be a basic distinction between (a) continuous activity and (b) activity which may be defined as episodic in that it regularly recurs in related episodes. For example, in 2CO 6:10 the fact of being glad may be related specifically to the occasions of being saddened, while in MAT 18:10 the focus of meaning is probably upon the continuous nature of the relation.
ACT 7:51 · 2CO 4:11 · 2CO 6:10 · TIT 1:12 · HEB 3:10 · 1PE 3:15 · 2PE 1:12
UBS Dictionary of the Greek New Testament © United Bible Societies, licensed CC BY-SA 4.0.
Thayer's Greek Lexicon
ἀεί, [see αἰών], adv., [fr. Hom. down], always; 1. perpetually, incessantly: Acts vii. 51; 2 Co. iv. 11; vi. 10; Tit.i.12; Heb.iii.10. 42. invariably, at any and every time when according to the circumstances something is or ought to be done again: Mk. xv. 8 [T WH om.] (at every feast); 1 Pet. iii. 15; 2 Pet. i. 12.
Mounce Concise Greek Dictionary
ἀεί aei 7x
always, for ever, constantly
Abbott-Smith Greek Lexicon
ἀεί, adv.,
[in LXX: Is 42:14 (מֵעוֹלָם) 51:13 (תָּמִיד), Ps 94 (95):10, al.;]
ever; of continuous time, unceasingly, perpetually: Ac 7:51, 2 Co 4:11 6:10, Tit 1:12, He 3:10.
Of successive occurrences, on every occasion (MM, VGT, s.v.): I Pe 3:15, II Pe 1:12.†
Liddell-Scott-Jones — Greek-English Lexicon
ἀεί (aei) — always. ἀεί, adverb ever, always, [Refs 8th c.BC+]; with other specifications of time, ἐμμενὲς αἰεί[Refs 8th c.BC+]; ἀ. καθ᾽ ἡμέραν, καθ᾽ ἡμέραν ἀ., ἀ. καὶ καθ᾽ ἡμέραν, ἀ. κατ᾽ ἐνιαυτόν, ἀ. διὰ βίου, etc., [Refs 5th c.BC+]; δεῦρ᾽ ἀεί until now, [Refs 5th c.BC+]; αἰεί κοτε, ποτε from of old, [Refs 5th c.BC+]; compare εἰσαεί:—with the Article, ὁ ἀ. χρόνος eternity, [Refs 5th c.BC+]; οἱ ἀ. ὄντες the immortals, [Refs 5th c.BC+] —but ὁ αἰ. βασιλεύων the king for the time being, [Refs 5th c.BC+]; ὁ αἰ. ἐντὸς γιγνόμενος every one as he got inside, [Refs 5th c.BC+]; τοῖσι τούτων αἰ. ἐκγόνοισι to their descendants for ever, [Refs 5th c.BC+], Et.Gud.z):
1. αἰεί, Epic dialect, Ionic dialect, poetical, and Early Attic dialect [Refs 4th c.BC+]
2. ἀεί [ᾰ three times in [Refs 8th c.BC+], ᾱ?~X Attic dialect] normal in Attic dialect Inscrr. from [Refs 4th c.BC+]
3. αἰέν, [Refs 8th c.BC+]
4. Doric dialect αἰές, [Refs 5th c.BC+]; also ἀές, [Refs]
5. Aeolic dialect αἶι(ν), ἄιν, Hdn.Gr.[same place];[Refs]
6. αἰέ, Hdn.Gr. [prev. cited]
7. ἀέ, [Refs 5th c.BC+] (ᾰἐ); compare ἀέ-ναος.
8. Boeotian dialect ἠί, [Refs 2nd c.AD+]
9. Tarentum dialect αἰή, [Refs]
II. τὸ ἀ. eternity, τὸ ἀ. τοῦτο οὐκ αἰώνιόν ἐστιν ἀλλὰ χρονικόν[Refs 1st c.AD+] = ἕως in Attic dialect is based on misinterpretation of such phrases as ἐς τόνδε αἰ. τὸν πόλεμον[Refs 5th c.BC+], cf. Latin aevum.)