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thirty

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noun thir·ty \ˈthər-tē\

Simple Definition of thirty

  • : the number 30

  • thirties : the numbers ranging from 30 to 39

  • : a set of years ending in digits ranging from 30 to 39

Source: Merriam-Webster's Learner's Dictionary

Full Definition of thirty

plural

thirties

  1. 1 — see number table

  2. 2 plural :  the numbers 30 to 39; specifically :  the years 30 to 39 in a lifetime or century

  3. 3 :  a sign of completion :  end —usually written 30 <wrote thirty on the last page of the story>

  4. 4 :  the second point scored by a side in a game of tennis

thirtieth

play \-tē-əth\ adjective or noun

thirty

adjective

thirty

pronoun, plural in construction

thirtyish

play \-ish\ adjective

Examples of thirty in a sentence

  1. The temperature outside is in the high thirties.

  2. He is in his thirties.



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

Rhymes with thirty


THIRTY Defined for Kids

1

thirty

play
adjective thir·ty \ˈthər-tē\

Definition of thirty for Students

  1. :  being three times ten




2

thirty

play
noun thir·ty

Definition of thirty for Students

  1. :  three times ten :  30




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