Definition of thirty
thirties
1 : a number equal to three times 10 — see number table
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
adjectivethirty
pronoun, plural in constructionExplore Merriam-Webster
Examples of thirty in a Sentence
The temperature outside is in the high thirties.
He is in his thirties.
Recent Examples of thirty from the Web
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In the nineteen-thirties, under Stalin, Soviet railway planners revived the proposal as part of the country’s industrialization drive, but the project went nowhere.
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Both are described as being in their early thirties and speaking with a slight accent.
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Thirty minutes after that, he's sentenced to life in prison without parole.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'thirty'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Origin and Etymology of thirty
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 12th century
Other Number-Related Terms
THIRTY Defined for English Language Learners
thirty
playDefinition of thirty for English Language Learners
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: the number 30
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thirties : the numbers ranging from 30 to 39
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: a set of years ending in digits ranging from 30 to 39
THIRTY Defined for Kids
Definition of thirty for Students
: being three times ten
Learn More about thirty
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See words that rhyme with thirty Spanish Central: Translation of thirty Nglish: Translation of thirty for Spanish speakers Britannica English: Translation of thirty for Arabic speakers
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