1 abiding, ceaseless, constant, deathless, endless, everlasting, immortal, infinite, interminable, never-ending, perennial, perpetual, sempiternal (literary) timeless, unceasing, undying, unending, unremitting, without end
2 deathless, enduring, everlasting, immortal, immutable, imperishable, indestructible, lasting, permanent
Antonyms
changing, ephemeral, evanescent, finite, fleeting, infrequent, irregular, mortal, occasional, perishable, random, rare, temporal, transient, transitory