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noun thir·ty \ˈthər-tē\

: the number 30

thirties : the numbers ranging from 30 to 39

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

plural thirties

Full Definition of THIRTY

— see number table
plural :  the numbers 30 to 39; specifically :  the years 30 to 39 in a lifetime or century
:  a sign of completion :  end —usually written 30 <wrote thirty on the last page of the story>
:  the second point scored by a side in a game of tennis
thir·ti·eth \-tē-əth\ adjective or noun
thirty adjective
thirty pronoun, plural in construction
thir·ty·ish \-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

jubilee, myriad, quarantine, score, twain

Rhymes with THIRTY

THIRTYISH Defined for Kids


adjective thir·ty \ˈthər-tē\

Definition of THIRTY for Kids

:  being three times ten



Definition of THIRTY for Kids

:  three times ten :  30


Next Word in the Dictionary: thirty–eightPrevious Word in the Dictionary: thirtoverAll Words Near: thirty
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