Synonyms of tough

1 Syllable

hard, firm, stiff, staunch, fit, firms, strong, best, mule, stout, strict, stern, tight, trying

2 Syllables

stony, firmest, viscid, crabbier, rugged, spunky, roughneck, dense, annoyer, coercer, crabby, rascals, carking, arduous, besting, firmer, strictest, feisty, awful, knotty, lifers, chuffy, sturdy, grafter, yardbird, stubborn, bullies, mumpish, upstream, hard-won, puissant, strenuous, bully, strongest, chuffier, molded, bullhead, fibrous, solid, dragger, slambang, slam-bang, tough-nut, stauncher, lustier, viscous, trojan, choicy, harder, varmint, grafters, annoyers, healthy, flinty, steeled, harriers, feistier, sterner, nastier, stonier, toilful, naughtiest, staunchest, stringent, brawnier, cardsharp, hardshell, robust, naughtier, hardest, stringiest, gangsters, strapping, grievous, gristlier, stalwart, gangster, taxing, stringy, mighty, stablest, brawny, knottier, wirier, rigid, spunkier, sturdier, stricter, brick-wall, well-built, wiry, lusty, muscled, rascal, stabler, ropy, cold-fish, stronger, nasty, nastiest, hardy, callous, sternest, naughty, gristly

3 Syllables

prisoner, demanding, hard-hearted, durable, robustuous, robustious, stiff-necked, thick-skinned, hellacious, unstirred, coldhearted, hard-as-nails, hardboiled, conscientious, kinetic, tormenter, viscose, vigorous, iceberg, unpitying, sobering, forbidding, hardline, rubbery, red-blooded, tormenters, backbreaker, valorous, effortful, difficult, coriaceous, ballbuster, glutinous, diuturnal, fine-grained, nonporous, prisoners, stabile, takeover, self-willed, unpliable, feelingless, nit-picking, uncordial, efficient, leathery, withstanding, muscular, rocklike, tenacious, seasoned, hard-nosed, unfeeling, exacting, hard-bitten, knockabout, laborious, internee, uncompliant, unyielding, hardened, take-charge, take-over, hard-driving, courageous, hardheaded, resistant, detainee, sinewy, herculean, resilient, reusable

4 Syllables

rosy-cheeked, unrelenting, burdensome, aversive, troublesome, tiresome, praiseworthy, unamusing, conditioned, unbreakable, ironhearted, tyrannical, oppressive, remorseless, difficile, long-continued, close-grained, depressive, obdurate, unamiable, boresome, iron-willed, unforgetful, bad-natured, case-hardened, unrepenting, reticular, intractable, infestive, unsavory, malevolent, cohesive, inflexible, leatherlike, heavy-duty, unbendable, energetic

5 Syllables

unhospitable, mucilaginous, unsympathetic, insensitive, casehardened, antagonizer, intimidator, superincumbent, incompressible, antagonizers, insusceptible, enervative, indigestible, unamenable, uncompromising, dispassionate

6 Syllables

uncompassionate, energy-consuming