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.
Or of my nephew at Catholic school in the nineties, having his curls measured for height, not length, by a ruler placed atop his head. Margaret Talbot, New Yorker, 21 July 2025 Baumgartner rose to fame as a skydiver and BASE jumper in the nineties and early aughts by attempting record-breaking jumps from prominent landmarks. Frederick Dreier, Outside Online, 17 July 2025 Averell Harriman, after leading Union Pacific and Brown Brothers Harriman, served as one of America’s greatest diplomats, unofficially advising presidents until his nineties. Christiaan Hetzner, Fortune, 15 July 2025 Advertisement Indians and Pakistanis, who remember a life before the Partition, before the borders, are in their nineties and dying fast. Sam Dalrymple, Time, 14 July 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 29 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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