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thirtieth

[ thur-tee-ith ]
/ ˈθɜr ti ɪθ /
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adjective
next after the twenty-ninth; being the ordinal number for 30.
being one of 30 equal parts.
noun
a thirtieth part, especially of one (1/30).
the thirtieth member of a series.
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Origin of thirtieth

before 900; thirty + -eth2; replacing Middle English thrittythe,Old English thrītegtha
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

How to use thirtieth in a sentence

British Dictionary definitions for thirtieth

thirtieth
/ (ˈθɜːtɪɪθ) /

adjective
(usually prenominal)
  1. being the ordinal number of thirty in counting order, position, time, etc: often written 30th
  2. (as noun)the thirtieth of the month
noun
  1. one of 30 approximately equal parts of something
  2. (as modifier)a thirtieth part
the fraction equal to one divided by 30 (1/30)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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