Synonyms to grim

adamant, adamantine, at a standstill, cast-iron, dour, firm, flintlike, flinty, frozen, granitelike, granitic, hard, hard-core, immobile, immotile, immotive, immovable, immutable, implacable, impliable, inductile, inelastic, inexorable, inextensible, inextensile, inextensional, inflexible, intractable, intractile, intransigent, iron, irreconcilable, irremovable, irresilient, lithic, marblelike, nonelastic, nonstretchable, obdurate, pat, petrified, petrogenic, relentless, rigid, rigorous, rock, rock-ribbed, slaty, standpat, stationary, steely, stern, stiff, stone, stubborn, unaffected, unalterable, unbending, unchangeable, uncompromising, unextendible, unextensible, unflexible, ungiving, unlimber, unmalleable, unmovable, unmoved, unmoving, unpliable, unpliant, unrelenting, unswayable, untractable, unyielding, anguished, aching, aggrieved, anxious, bleeding, bored, bruised, careworn, cheerless, cut, depressed, disgusted, doleful, dolorous, dumb with grief, grief-stricken, griefful, grieved, grievous, hurt, in grief, injured, joyless, lamentable, lugubrious, mauled, mournful, nauseated, nauseous, pained,