Webster's Revised Unabridged Dictionary · 1913

Impenitent

Impenitent , adjective

[Latin impaenitens; pref. im- not + paenitens penitens: compare French impénitent. See Penitent.]

Not penitent; not repenting of sin; not contrite; of a hard heart.
They... died impenitent. — Milton
A careless and impenitent heart. — Bp. Hall

Impenitent , noun

One who is not penitent. [Rare]