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.
When people can only make it to their early thirties, what’s the point of having kids? George Yang, Rolling Stone, 23 Apr. 2025 And my grandparents and my great grandparents and cousins and aunts and everything, from the thirties and the twenties and the forties. Mike Fleming Jr, Deadline, 21 Apr. 2025 While Lincoln was a relatively young man in his late thirties, Karl Marx boasted that the Communist specter was haunting Europe. Liz Tracey, JSTOR Daily, 24 Mar. 2025 Salah and Van Dijk were in their early thirties, and while still performing at an elite level, Liverpool were conscious that their previous contracts had been agreed when both were at the peak of their powers. Simon Hughes, New York Times, 11 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

Browse Nearby Words

Cite this Entry

“Thirty.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thirty. Accessed 4 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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