Synonyms and related words :
Philistine, anneal, apathetic, asleep, backed, benumbed, brazen, brutalize, calcified, calcify, calloused, case harden, case-hardened, cold, cold of heart, coldblooded, coldhearted, conscienceless, cornify, crusted, crusty, crystallized, dead, deadened, dull, firm, flinthearted, flinty, fossilize, fossilized, granulated, hard, hard of heart, hard-boiled, hard-nosed, harden, hardened, hardhearted, heartless, hornified, impassible, impenitent, imperceptive, impercipient, impervious, incrusted, indifferent, indurate, indurated, insensate, insensible, insensitive, insentient, insolent, inure, inured, lapidified, lapidify, lithify, lost to shame, numb, numbed, obdurate, obtuse, ossified, ossify, pachydermatous, petrified, petrify, proof against, reinforced, rigidified, sclerotic, seared, set, shameless, solidified, steel, steeled, steeled against, steely, stiffened, stony, stonyhearted, strengthened, temper, thick-skinned, thick-witted, tough, toughen, toughened, unabject, unblushing, uncaring, uncompassionate, uncontrite, unemotional, unfeeling, unfelt, unmelted, unmerciful, unnatural, unperceptive, unrepentant, unrepenting, unresponsive, unsoftened, unsympathetic, untouched, vitrified, vitrify