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thirty

play
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

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

thir·ti·eth play \-tē-əth\ adjective or noun
thirty adjective
thirty pronoun, plural in construction
thir·ty·ish play \-ish\ adjective

Examples of thirty

  1. The temperature outside is in the high thirties.

  2. He is in his thirties.



Origin 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



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