stout, stiff, self-opinionated, self-willed, fixed, situated, habitual, inexperienced, located, inaccessible, dictated, pigheaded, firm, primed, strong, headstrong, bad, impious, undemonstrative, cold, shameless, rugged, stiff-necked, attitude, obdurate, pat, abandoned, burned, contemptuous, placed, impassive, inflexible, laid, irredeemable, habituated, impenetrable, mulish, opinionated, degenerate, uncompromising, pertinacious, profane, unrelenting, determined, unyielding, unbending, resistant, willful, cast-iron, stonyhearted, neutral, stubborn, unaccustomed, controlled, adamantine, pugnacious, trained, reprobate, ossified, sunbaked, cold-hearted, incorrigible, sturdy, burnt, intransigent, accustomed, inconvincible, perverse, irreligious, chronic, blasphemous, hardheaded, inured, adamant, immovable, unresponsive, restrained, hard-nosed, disdainful, bullheaded, blank, rigid, annealed, benumbed, indurate, inveterate, implacable, fit, depraved, treated, vigorous, cruel, compassionless, hard-bitten, baked, irreverent, case-hardened, uncaring, insensible, enured, irreclaimable, dogged, untouched, lost, sacrilegious
hardened (part of speech: verb)
congealed (part of speech: verb)
impenitent (part of speech: adjective)
insensitive (part of speech: adjective)
callous, heartless, hardhearted, insensitive, hard, stony, dispassionate, nonchalant, indifferent, passionless, uncompassionate, detached, unfeeling, ruthless, aloof, objective, cold-blooded, unsympathetic, passive, cool, blunt, anesthetized, tough, unconcerned, numb, unemotional, emotionless, apathetic, hard-boiled
strengthened (part of speech: verb)
- He smiled kindly at her, but his face hardened again as he turned once more to Hubert. - "By What Authority?", Robert Hugh Benson.
- He had been hardened by many a fight in the law courts, and he knew how little such words might mean. - "The Day of Judgment", Joseph Hocking.
- They were naturally coarse, hardened adventurers, and it was such that Hawthorne chiefly came in contact with in his official business. - "The Life and Genius of Nathaniel Hawthorne", Frank Preston Stearns.