Synonyms of eternal

1 Syllable

vast

2 Syllables

come-through, deathless, undying, long-term, always, boundless, constant, endless, lasting, vastest, longterm, vaster, spread-out, yearlong, termless

3 Syllables

enduring, ceaseless, jesuitic, dateless, unfleshly, unfailing, immortal, relentless, incessant, unceasing, continuous, perennial, celestial, longstanding, unchanging, timeless, continual, unending, persistent, perpetual, unchanged, stretched-out, immense, steady-going, ageless, divined, olympian, elysian, empyral, unplumbed, transcendent, continued, unended, round-the-clock, aeonian, unwaning, day-and-night, unbroken, unfading, abiding, forever, permanent

4 Syllables

suprahuman, nonmaterial, unphysical, unmeasured, unremitting, discarnate, immutable, never-ending, immemorial, around-the-clock, oft-repeated, measureless, all-embracing, everlasting, infinite, never-ceasing, phoenixlike, perdurable

5 Syllables

unfathomable, supermundane, supranatural, supramundane, self-perpetuating, metaphysical, amaranthine, supertemporal, indefinite, uninterrupted, interminate, illimitable, interminable, imperishable, indestructible