Being or seeming to be without an end or limit; boundless.(adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "unending" in a sentence
"Shaggy gray-beards, sixty feet from trough to crest, leapt out of the windward murky gray, and in unending procession rushed upon the"
"I'll admit I was thinking earlier that being stuck in unending, unbearable summer must be just as bad as the same for winter (and probably worse for me, as I cannot manage heat at all), but ... still."
"A good average pile, by the time it was delivered on the ground, cost a twenty-dollar gold piece, and these piles were used in unending thousands."