thirty

noun

thir·​ty ˈthər-tē How to pronounce thirty (audio)
plural thirties
1
: a number equal to three times 10 see Table of Numbers
2
thirties plural : the numbers 30 to 39
specifically : the years 30 to 39 in a lifetime or century
3
: a sign of completion : end
usually written 30
wrote thirty on the last page of the story
4
: the second point scored by a side in a game of tennis
thirtieth adjective or noun
thirty adjective
thirty pronoun, plural in construction
thirtyish adjective

Examples of thirty in a Sentence

The temperature outside is in the high thirties. He is in his thirties.
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.
Lionel drifts through Europe in his twenties and thirties, building a new life of profound success and happiness, and experiencing new loves. Anthony D'alessandro, Deadline, 22 May 2025 Now, in my thirties, family is my priority above all else. Sara Vallone, Miami Herald, 12 May 2025 It is not specified in the novel, Adventures of Huckleberry Finn, but Jim is usually taken by scholars to be in his late twenties or early thirties. John Jeremiah Sullivan, Harpers Magazine, 29 Apr. 2025 However, Cooper thought Premier League experience was vital, so brought in Jordan Ayew and Bobby De Cordova-Reid, both in their thirties. Rob Tanner, New York Times, 21 Apr. 2025 See All Example Sentences for thirty

Word History

Etymology

Middle English thritty, from thritty, adjective, from Old English thrītig, from thrītig group of 30, from thrīe three + -tig group of ten; 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 thirty was before the 12th century

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Cite this Entry

“Thirty.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thirty. Accessed 29 May. 2025.

Kids Definition

thirty

noun
thir·​ty ˈthərt-ē How to pronounce thirty (audio)
plural thirties
1
: a number equal to three times 10 see number
2
plural : the numbers 30 to 39
especially : the years 30 to 39 in a lifetime or century
thirtieth noun or adjective
thirty adjective or pronoun

More from Merriam-Webster on thirty

Last Updated: - Updated example sentences
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