Synonyms for Tenacious:

adj.

adhesive (adjective)
Clinging.
all (adjective)
coherent.
brave (adjective)
plucky.
courageous (adjective)
fearless.
obstinate (adjective)
rigid, obdurate, hard-nosed, pertinacious, stubborn, hidebound, inelastic, unyielding, adamant, unbendable, uncompromising, obstinate, contrary, hardheaded, inflexible, resolute, bull-headed, brass-bound, bigoted, Pig-headed, bovine, mulish.
persevering (adjective)
lasting, brave, stoical, persistent, indomitable, unwavering, patient, surviving, abiding, indefatigable, persevering, steadfast, unflagging, unfaltering, enduring.
resolute (adjective)
intent, implacable, spunky, pertinacious, bold, firm, tireless, headstrong, relentless, decisive, fearless, constant, strong-willed, unbending, stubborn, hearty, earnest, true, faithful, resolute, ruthless, uncompromising, steady, reliable, steadfast, unyielding, decided, diligent, unshakeable, determined, insistent, devoted, set, indomitable, willing, inexorable, plucky, deliberate, strong-minded, committed, persistent, iron-willed, serious, loyal, persevering, unflinching, stern, bullheaded, indefatigable, dauntless, dedicated, unchangeable, zealous, courageous, staunch, tough, steely, resolved, dogged, thorough, unwavering, valiant.
sticky (adjective)
inseparable, glutinous, waxy, viscid, secure, viscous, Resisting, adhesive, gummy.
strong (adjective)
iron-willed.
strong, unyielding (adjective)
persevering, resolute, true, staunch, pertinacious, purposeful, fast, persistent, relentless, firm, tough, set, tight, stubborn, adamant, spunky, mulish, strong-willed, dogged, obdurate, Clinging, steadfast, coherent, inflexible, determined, retentive, obstinate.
tenacious (adjective)
stony, unflagging, dogged, devoted, bullheaded, plucky, stiff, insistent, hard, bold, flintlike, undaunted, resolute, faithful, spunky, enduring, indomitable, indefatigable, staunch, dauntless, strong-willed, steadfast, persistent, hearty, obdurate, obstinate, decisive, bulldogged, tireless, fervent, courageous, brave, true, diligent, tough, strong, determined, headstrong, stubborn, persevering.

n.

unchanging, unvarying, for good, whatever happens, invariable, irreversible, final. motivated, resist, pigheaded, perverse, competitive, ambitious, willful, stiff-necked, sedulous, driven. secure, free, tight, Clinging, fast, tighten. persistent (noun)
purposeful.
tenacious (noun)
dogged, pertinacious, long, dour, bulldog, adhesive, unyielding, stubborn, retentive, coherent.

Other synonyms:

Clinging. stiff-necked, pigheaded. willful, perverse. tight, secure. fast. Other relevant words:
perverse, sedulous, Resisting, unchanging, purposeful, retentive, fast, pigheaded, secure, glutinous, Clinging, stiff-necked, willful, waxy, adhesive, tight, inseparable, viscous, dour, irreversible, bulldogged, viscid, bulldog, gummy, coherent, sticky, long.

Usage examples for tenacious

  1. He had to flee immediately, and, after wandering about for some time in a disguise, one of the features of which is stated to have been a false nose, he was seized on his way to the Reichstag which was being held at Speier in 1526. Tenacious of his property to the last, he had hoped to obtain restitution of his rights from the assembled estates of the empire. – German Culture Past and Present by Ernest Belfort Bax
  2. There was something uncanny about its great- eyed silence and its tenacious hold on life. – The Dop Doctor by Clotilde Inez Mary Graves
  3. That morbid and tenacious curiosity once more got hold of him. – The Nest of the Sparrowhawk by Baroness Orczy