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
thirty
adjective
thirty
pronoun, plural in construction
Examples of thirty in a Sentence
The temperature outside is in the high thirties.
He is in his thirties.
Recent Examples on the Web
By the thirties, however, light pollution had made the center of Rome inhospitable to the observatory, and the Pope—now Pius XI—offered the use of Castel Gandolfo as a future base of operations.
—
Rebecca Mead, New Yorker, 28 July 2025
Once that is complete, the prefrontal cortex fully matures, and so, in their thirties, people begin to reflect on their goals and purpose.
—Alyce Collins, MSNBC Newsweek, 24 July 2025
One of the custodians, a Black man in his thirties, knew how to tune it and offered to set it up.
—David Kushner, Rolling Stone, 20 July 2025
The two would walk around the set holding hands, and smoked cigarettes together outside their trailers, Gwyneth holding hers like a thirties movie star.
—Liz McNeil, People.com, 16 July 2025
See All Example Sentences for thirty
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Rebecca Mead, New Yorker, 28 July 2025
Once that is complete, the prefrontal cortex fully matures, and so, in their thirties, people begin to reflect on their goals and purpose.
—Alyce Collins, MSNBC Newsweek, 24 July 2025
One of the custodians, a Black man in his thirties, knew how to tune it and offered to set it up.
—David Kushner, Rolling Stone, 20 July 2025
The two would walk around the set holding hands, and smoked cigarettes together outside their trailers, Gwyneth holding hers like a thirties movie star.
—Liz McNeil, People.com, 16 July 2025
See All Example Sentences for thirty
Cite this Entry
“Thirty.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thirty. Accessed 10 Aug. 2025.
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