Lexical Definition

‎νυνί‎ nyní (noo-nee') now G:ADV
a prolonged form of ‎νῦν‎ for emphasis

now.

Usage: 1 form in 20 verses
Form Translated As     In Verse(s)
νυνὶ In that case Rom.7.17
now Acts.22.1Acts.24.13Rom.3.21Rom.6.22Rom.7.6Rom.15.23Rom.15.251Cor.12.181Cor.13.131Cor.15.202Cor.8.112Cor.8.22Eph.2.13Col.1.22Col.3.8Phlm.1.9Phlm.1.11Heb.8.6Heb.9.26

Abbott-Smith

νυνί, an Attic strengthened form of νῦν (in cl. always of time, and most often strictly of the pres.), [in LXX : Jb5, Pss2, II, IV Mac4, Ep. Je.*;]
now;
1. of time: c. praes., Ac 24:13, Ro 15:23, 25, I Co 13:13, II Co 8:11, 22, Phm 9, 11; c. pf., Ro 3:21; c. pret., Ro 6:22 11:30 (WH, mg.) 7:6, Eph 2:13, Col 1:21 3:8; ἡ ν. ἀπολογία, Ac 22:1.
2. Of logical sequence (not so in cl.): Ro 7:17, I Co 5:11 (νῦν, WH) 12:18 (νῦν, WH, txt.) 15:20, He 8:6 (νῦν, WH, txt.), He 9:26 (cf. WM, 24, 579n).†

Abbott-Smith References

Book Refs
Acts 22:1 · 24:13
Romans 3:21 · 6:22 · 7:6 · 7:17 · 11:30 · 15:23 · 15:25
1 Corinthians 5:11 · 12:18 · 13:13 · 15:20
2 Corinthians 8:11 · 8:22
Ephesians 2:13
Colossians 1:21 · 3:8
Philemon 1:9 · 1:11
Hebrews 8:6 · 9:26

Liddell-Scott-Jones

form of: νῦν

νυνί,

Attic dialect form of νῦν, strengthened by - demonstrative, now, at this moment, mostly of the present, [Refs 5th c.BC+]: less frequently with past tenses, ὧν ν. διέβαλλε [Refs 5th c.BC+]: also with future, ν. δὲ πειράσομαι [Refs 5th c.BC+]: with aorist imperative, ν. μεταγνώτω [Refs 5th c.BC+]: rarely in the sense, as the case stands [Refs 5th c.BC+]; νυνδί, for νυνὶ δέ, [Refs 4th c.BC+]; compare νυνγαρί, for νυνὶ γάρ, [Refs]