The ordinal number matching the number 100 in a series.(noun)
One of 100 equal parts.(noun)
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 "hundredth" in a sentence
"[Page 422] this hundredth is too good for anybody I ever saw."
"It was the fourth day, and I was lounging in the camp's little market, improving my Persian by learning the ninety-nine names of God (only the Bactrian camels know the hundredth, which is why they look so deuced superior) from an Astrabad caravan-guard-turned-murderer, when Kutebar came in a great bustle to take me to Yakub Beg at once."
"I mean upper 1 percent, or what's called the hundredth percentile on intelligence tests."