Invincible

a.

1.

Incapable of being conquered, overcome, or subdued; unconquerable; insuperable; as, an invincible army, or obstacle. Lead forth to battle these my sons Invincible. - Milton.

Adj.

1.

invincible - incapable of being overcome or subdued; "an invincible army"; "her invincible spirit" Synonyms: unvanquishable, unbeatable

assiduous, beyond compare, beyond comparison, calculable, constant, continuing, deathless, dependable, diligent, dogged, easily first, enduring, facile princeps, faithful, faithworthy, fast, firm, immortal, immutable, impassable, impenetrable, imperishable, inalterable, incomparable, incontestable, incorruptible, indefatigable, indelible, indestructible, industrious, ineffaceable, ineradicable, inexpugnable, inextinguishable, inimitable, insistent, insuperable, inviolable, invulnerable, irresistible, lasting, loyal, matchless, never-tiring, nonperishable, nulli secundus, obstinate, overpowering, overwhelming, patient, patient as Job, peerless, permanent, perseverant, persevering, persistent, persisting, pertinacious, plodding, plugging, predictable, preoccupied, quenchless, rapt, relentless, reliable, resistless, resolute, second to none, secure, sedulous, single-minded, sleepless, slogging, solid, sound, stable, staunch, steadfast, steady, stubborn, substantial, sui generis, sure, surefire, tenacious, tireless, trustworthy, trusty, unabating, unapproachable, unapproached, unassailable, unattackable, unbeatable, undampable, undaunted, undefeatable, undefeated, undestroyable, undiscouraged, undrooping, undying, unequaled, unexampled, unexcelled, unfailing, unfaltering, unflagging, unflinching, unintermitting, uninterrupted, unique, unmatchable, unmatched, unnodding, unparagoned, unparalleled, unpeered, unquenchable, unrelaxing, unrelenting, unremitting, unrivaled, unsleeping, unstoppable, unsubduable, unsurmountable, unsurpassable, unsurpassed, unswerving, untiring, untouchable, unwavering, unwearied, unwearying, unwinking, unyielding, utterly attentive, weariless, well-founded, well-grounded, without equal, without parallel