[1] : The Collaborative International Dictionary of English v.0.48

undying \undy"ing\, a.
   not dying; imperishable; unending; immortal; as, the undying
   souls of men.
   1913 webster

[2] : WordNet (r) 2.0

undying
     adj : never dying; "his undying fame" syn: deathless
see also:
deathless 

[3] : Moby Thesaurus II by Grady Ward, 1.0

39 moby thesaurus words for "undying":
   abiding, amaranthine, continuing, continuous, deathless, embalmed,
   ever-fresh, everlasting, fadeless, frozen, immortal, imperishable,
   impregnable, incorruptible, indefatigable, indelible,
   indestructible, ineffaceable, ineradicable, inexpugnable,
   inextinguishable, interminable, invincible, invulnerable,
   never-dying, nonperishable, persistent, quenchless, remaining,
   staying, steady, sticking, sustained, unceasing, undampable,
   undestroyable, unfading, unquenchable, unremitting

Undying >> U Words
Undying, definition of term: Undying
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