Quick Definition
ἐπείπερ Cj. since indeed, seeing that
Strong's Definition
since indeed (of cause)
Derivation: from G1893 (ἐπεί) and G4007 (περ);
KJV Usage: seeing
Thayer's Greek Lexicon
ἐπεί-περ, conjunction, (ἐπεί, πέρ). since indeed, since at all events; [it introduces a “known and unquestioned certainty 7: Ro. iii. 30 RG (but L Tr εἴ rep, TWH Cf. Hermann ad Vig. p. 784; [Baumlein p. 204; Fr. the Tragg. down. ]* W. 448 (417).
Mounce Concise Greek Dictionary
Abbott-Smith Greek Lexicon
ἐπεί-περ conj., since indeed: Ro 3:30 (Rec.; εἴπερ, WH).†
Moulton & Milligan — Vocabulary of the Greek NT
ἐπείπερ. For ἐπείπερ, which is read in the TR of Rom 3%, cf. P Par 63188 (p.c. 165) (=P Petr III. p. 34) ἐπείπερ ὑμᾶς δεῖ συνεχέστερον ὑπὲρ τῶν α[ὐτ]ῶν ὑπομιμνήσκειν, ‘since it is necessary to keep reminding you continuously about the | same things” (Mahaffy), and P Oxy XII. 14694 (A.p. 298) ἐπείπερ ἐὰν πλεονεξία τις προχωρήσῃ καθ᾽ [ἡμῶν Be | ἀδυναμείαν ἀνᾳπόστατοι καταστη[σ]όμεθα, “since, if any advantage of us is taken, our weakness will leave us no | escape” (Edd.).
Liddell-Scott-Jones — Greek-English Lexicon
ἐπείπερ (epeiper) — since. ἐπείπερ or ἐπεί περ, see at {ἐπεί} [Refs 5th c.BC+]