Synonyms for Never-failing:

• adj.

  •firm (adjective)
  • bound,
  • persistent,
  • resolved,
  • inflexible,
  • hang tough,
  • resolute,
  • steady,
  • constant,
  • unflinching,
  • unshaken,
  • flat,
  • stand pat,
  • obdurate,
  • abiding,
  • unbending,
  • strict,
  • fixed,
  • strong,
  • going,
  • explicit,
  • steadfast,
  • set,
  • stated,
  • stable,
  • true,
  • settled,
  • intent,
  • consistent,
  • unyielding,
  • specific,
  • established,
  • staunch,
  • enduring,
  • unshakable,
  • exact,
  • bent,
  • Stipulated,
  • persevering,
  • determined,
  • adamant,
  • prevailing,
  • unchangeable,
  • tenacious.
  •fixed (adjective)
  • level,
  • unmodifiable,
  • limited,
  • inveterate,
  • unmovable,
  • rooted,
  • definitive,
  • decided,
  • precise,
  • certain,
  • agreed,
  • definite,
  • changeless,
  • restricted,
  • narrow,
  • planned,
  • arranged,
  • inalterable,
  • in the bag,
  • confirmed,
  • circumscribed,
  • determinate,
  • still,
  • defined,
  • rigged.
  •foolproof (adjective)
  • sure-fire,
  • tested,
  • idiot-proof,
  • safe,
  • dependable,
  • reliable,
  • guaranteed,
  • FAILSAFE,
  • unassailable,
  • tried,
  • goofproof,
  • unerring,
  • flawless,
  • fail-safe,
  • perfect,
  • faultless.
  •infallible (adjective)
  • foolproof.
  •steadfast (adjective)
  • intense,
  • ardent,
  • faithful,
  • liege,
  • tried-and-true,
  • immovable,
  • allegiant,
  • rigid,
  • unswerving,
  • stubborn,
  • immobile,
  • fast,
  • relentless,
  • true-blue,
  • single-minded,
  • inexorable,
  • dedicated.
  •steady (adjective)
  • stabile,
  • patterned,
  • even,
  • durable,
  • uniform,
  • solid,
  • substantial,
  • unvarying,
  • regular,
  • unchanging,
  • equable,
  • steady-going.
  •sure (adjective)
  • indubitable,
  • genuine,
  • positive,
  • unequivocal,
  • valid,
  • Persuaded,
  • incontrovertible,
  • unquestionable,
  • indisputable,
  • assured,
  • uncompromising,
  • convinced,
  • real,
  • incontestable,
  • satisfied,
  • confident,
  • clear,
  • telling,
  • undeniable,
  • doubtless,
  • convincing.
  •undoubting (adjective)
  • un doubting,
  • un-doubting.
  •unfailing (adjective)
  • same,
  • come-through,
  • straight,
  • loyal,
  • rock solid,
  • Delivering,
  • inexhaustible,
  • continuous,
  • unflagging,
  • bottomless,
  • absolute,
  • dyed-in-the-wool,
  • boundless,
  • unlimited,
  • there,
  • trustworthy,
  • assiduous,
  • invariable,
  • counted on,
  • continuing,
  • continual,
  • infallible,
  • surefire,
  • diligent,
  • unrelenting.
  •unfaltering (adjective)
  • tireless,
  • mulish,
  • unflappable,
  • meaning business,
  • pigheaded,
  • bound and determined,
  • bent on,
  • indefatigable,
  • untiring.
  •unqualified (adjective)
  • sheer,
  • unrestrained,
  • simple,
  • rank,
  • unrestricted,
  • unmitigated,
  • flat out,
  • downright,
  • total,
  • categorical,
  • blasted,
  • express,
  • complete,
  • unadulterated,
  • thorough,
  • thoroughgoing,
  • blessed,
  • out-and-out,
  • utter,
  • consummate,
  • confounded,
  • infernal,
  • unreserved,
  • entire,
  • unconditional.
  •unwavering (adjective)
  • pat.
  •wholehearted (adjective)
  • enthusiastic,
  • whole-hearted.
  •wholehearted/whole-hearted (adjective)
  • emphatic,
  • heartfelt,
  • unstinting,
  • fervent,
  • zealous,
  • authentic,
  • bona fide,
  • earnest,
  • impassioned,
  • passionate,
  • frank,
  • warm,
  • candid,
  • committed,
  • devoted,
  • serious,
  • unfeigned,
  • hearty.

• Other synonyms:

  •Other relevant words:
  • perennial,
  • immortal,
  • permanent,
  • unending,
  • unquestioning,
  • undoubting,
  • interminable,
  • unfading,
  • never-ending,
  • ceaseless,
  • unceasing,
  • eonian,
  • perpetual,
  • imperishable,
  • sempiternal,
  • endure,
  • endless,
  • timeless,
  • undying,
  • everlasting,
  • eternal.

Antonyms for Never-failing:

• adj.

  • firm
    uncertain, changeable, afraid, obscure, easy-going, irresolute, flexible, false, indefinite, unfixed, disloyal, supple, inconstant, unstable, unsteady, undecided, soft, untrue, vague, wavering, yielding, inconsistent, slack, Surrendering, alterable, varying, wobbly, fickle, unsettled, loose, moving, untrustworthy, unreliable, broken, weak.
  • fixed
    questionable, impermanent, variable, unestablished, inexact, imprecise, in disrepair, unlimited.
  • steadfast
    willing, pliable, pliant, dishonest.
  • steady
    irregular, imbalanced, movable, vulnerable, intermittent, unfaithful, different, discontinuous, undependable.
  • sure
    unconfident, doubtful, unself-confident, unsure, swerving, dubious, humbled, doubted.
  • unfailing
    failing, changing, limited.
  • unfaltering
    faltering.
  • unqualified
    qualified, competent, temporary, conditional, prepared, tentative, ready.
  • wholehearted/whole-hearted
    unenthusiastic, halfhearted, insincere, disinterested.