THESAURUS
buff, cartilaginous, chewy, cohesive, coriaceous, durable, fibrous, gristly, hard, hardy, lasting, leather, leatherlike, leathern, resistant, ropy, sinewy, stiff, stringy, strong, stubborn, tenacious, tough, tough as leather, untiring, vigorous, viscid, wiry
ROGET THESAURUS
Tenacity
N
tenacity, toughness, strength, (cohesion), grip, grasp, stickiness, (cohesion), sequacity, stubbornness (obstinacy), glue, cement, glutinousness, sequaciousness, viscidity, (semiliquidity), leather, white leather, whitleather, gristle, cartilage, unbreakability, tensile strength, tenacious, tough, strong, resisting, sequacious, stringy, gristly cartilaginous,
leathery, coriaceous, tough as whitleather, stubborn, unbreakable, indivisible, atomic.