ninety

noun

nine·​ty ˈnīn-tē How to pronounce ninety (audio)
plural nineties
1
: a number equal to nine times 10 see Table of Numbers
2
nineties plural : the numbers 90 to 99
specifically : the years 90 to 99 in a lifetime or century
She's in her nineties.
ninetieth adjective or noun
ninety adjective
ninety pronoun, plural in construction

Examples of ninety in a Sentence

During the nineties, he was going to college and working part-time.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
By the late nineties, relatively wealthier nations had childhood-vaccination rates of more than ninety per cent, and were seeing few cases of vaccine-preventable diseases. Rivka Galchen, New Yorker, 27 June 2025 In the nineties, MAC Cosmetics was the new kid on the block. Essence, 24 June 2025 Gamers of the nineties will lap this up, especially when a Pac-Man wannabe starts talking about drugs. Joshua Lamb, Forbes.com, 24 June 2025 What keeps me going is what kept my subjects flourishing in their seventies, eighties or nineties. Marc Weingarten, Los Angeles Times, 21 June 2025 See All Example Sentences for ninety

Word History

Etymology

Middle English ninety, adjective, from Old English nigontig, short for hundnigontig, from hundnigontig, noun, group of 90, from hund-, literally, hundred + nigon nine + -tig group of 10; akin to Old English tīen ten

First Known Use

before the 12th century, in the meaning defined at sense 1

Time Traveler
The first known use of ninety was before the 12th century

Cite this Entry

“Ninety.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ninety. Accessed 5 Jul. 2025.

Kids Definition

ninety

noun
nine·​ty ˈnīnt-ē How to pronounce ninety (audio)
plural nineties
1
: a number equal to nine times 10 see number
2
plural : the numbers 90 to 99 and specifically the years 90 to 99 in a lifetime or century
ninetieth adjective or noun
ninety adjective or pronoun

More from Merriam-Webster on ninety

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