Adjective : a poet of enduring greatness.    From Dictionary.com. 

She realized, first of all, the enduringness of the marbles.    From Wordnik.com.  [Mae Madden] Reference

Despite vinyl being the most standard material for these record discs, there were still some issues with its enduringness.    From Wordnik.com.  [Figure Vinyl | SciFi, Fantasy & Horror Collectibles] Reference

Her characters - - their lives, their triumphs, and their failures – speak to the enduringness of love and truth and the dominance of the human spirit.    From Wordnik.com.  [Review] Reference

Again, clearness is one of the first elements in style, and on poetry attaining clearness, depends, in great measure, its enduringness in the future.    From Wordnik.com.  [The Poetry Of Robert Browning] Reference

And we think happiness has pleasure mingled with it, but the activity of philosophic wisdom is admittedly the pleasantest of virtuous activities; at all events the pursuit of it is thought to offer pleasures marvellous for their purity and their enduringness, and it is to be expected that those who know will pass their time more pleasantly than those who inquire.    From Wordnik.com.  [The NICOMACHEAN ETHICS] Reference

Sever themselves and madly sweep the sky, "gives to the passenger a sense of the enduringness of the pageant upon which those seeing eyes looked more than three centuries ago.    From Wordnik.com.  [William Shakespeare] Reference

Not for the sake of love, but for free breathing; and her utterance of it was to insure life and enduringness to the wish, as the yearning of a mother on a drowning ship is to get her infant to shore.    From Wordnik.com.  [Complete Project Gutenberg Works of George Meredith] Reference

Of course by toughness I mean enduringness.    From Wordnik.com.  [The Jacket (Star-Rover)] Reference

Of course, by toughness I mean enduringness.    From Wordnik.com.  [Chapter 19] Reference