Webster's Revised Unabridged Dictionary · 1913

Incorrigible

Incorrigible , adjective

[Latin incorrigibilis: compare French incorrigible. See In- not, and Corrigible.]

Not corrigible; incapable of being corrected or amended; bad beyond correction; irreclaimable; as, incorrigible error.
Incorrigible fools. — Dryden

Incorrigible , noun

One who is incorrigible; a person whose persistent bad behavior cannot be changed; especially, a hardened criminal; as, the perpetual imprisonment of incorrigibles; incorrigible and disruptive children need to be placed in a separate classroom.