Lexical Definition

‎σκληρύνω‎ sklērýnō (sklay-roo'-no) to harden G:V
from ‎σκληρός‎

harden.

Usage: 12 forms in 39 verses
Form Translated As     In Verse(s)
ἐσκληρύνοντο were hardened Acts.19.9
σκληρύνητε harden LXX.2Chr.30.8LXX.Ps.95.8
shall harden Heb.3.8Heb.3.15Heb.4.7
σκληρύνει He hardens Rom.9.18
σκληρυνώ will harden LXX.Exod.4.21LXX.Exod.7.3LXX.Exod.14.4LXX.Exod.14.17
σκληρυνομένη hardening LXX.Judg.4.24
σκληρυνθῇ may be hardened Heb.3.13
σκληρυνθείη may it be hardened LXX.Ps.90.6
σκληρυνείτε harden LXX.Deut.10.16
εσκληρύνθη hardened LXX.Gen.49.7
was hardened LXX.Exod.7.22LXX.Exod.8.19LXX.Exod.9.35LXX.2Sam.19.43
εσκλήρυνε hardened LXX.Exod.9.12LXX.Exod.10.27LXX.Exod.11.10LXX.Deut.2.30LXX.1Kgs.12.4LXX.2Chr.10.4
he hardened LXX.Exod.13.15LXX.2Chr.36.13
lord hardened LXX.Exod.10.20LXX.Exod.14.8
εσκλήρυνασ You hardened LXX.2Kgs.2.10LXX.Isa.63.17
εσκλήρυναν they hardened LXX.2Kgs.17.14LXX.Neh.9.16LXX.Neh.9.17LXX.Neh.9.29LXX.Jer.7.26LXX.Jer.17.23LXX.Jer.19.15

Abbott-Smith

σκληρύνω (< σκληρός), [in LXX chiefly for קשׁה hi., also for חזק ;]
to harden. Metaph., to harden, make stubborn: c. acc. pers., Ro 9:18; τ. καρδίας (Ps 94 (95):8*), He 3:8, 15 4:7. Pass., to become hardened: Ac 19:9, He 3:13.†

Abbott-Smith References

Book Refs
Psalms 95:8*
Acts 19:9
Romans 9:18
Hebrews 3:8 · 3:13 · 3:15 · 4:7

Liddell-Scott-Jones

σκληρύνω-ύνω,

harden, opposed to μαλάσσω, [Refs 5th c.BC+]:—passive, with perfect ἐσκλήρυσμαι [Refs 5th c.BC+], to be hardened, grow hard, [Refs 4th c.BC+]

__2 metaphorically, σ. τὴν καρδίαν τινός harden his heart, [LXX+NT]:—passive, [LXX]

LSJ Scripture Refs: LXX.Exod.7.3Heb.3.8Rom.9.18