Noun
deathlessness (usually uncountable, plural deathlessnesses)
The state of being deathless; eternity; immortality.
A human act once set in motion flows on forever to the great account. Our deathlessness is in what we do, not in what we are. George Meredith
Better a life like a falling star, bright across the dark, than a deathlessness which can see naught above or beyond itself. Poul Anderson
And lastly there is the oldest and deepest desire, the Great Escape: the Escape from Death. Fairy-stories provide many examples and modes of this ... Fairy-stories are made by men not by fairies. The Human-stories of the elves are doubtless full of the Escape from Deathlessness. J. R. R. Tolkien