thirtieth

American  

[thur-tee-ith] / ˈθɜr ti ɪθ /

adjective

1. next after the twenty-ninth; being the ordinal number for 30.

2. being one of 30 equal parts.

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noun

thirtieths plural

1. a thirtieth part, especially of one (1/30).

2. the thirtieth member of a series.

thirtieth British  

/ ˈθɜːtɪɪθ /

adjective

1. (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

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noun

1. 1. one of 30 approximately equal parts of something

   2. ( as modifier )

      a thirtieth part

2. the fraction equal to one divided by 30 ( 1/ 30 )

Other Word Forms

Noun Inflected Forms

• thirtieths
  plural

Etymology

Origin of thirtieth

before 900; thirty + -eth ²; replacing Middle English thrittythe, Old English thrītegtha

Example Sentences

“Somewhere it dawns on a politician. Tenth year? Twentieth year? Thirtieth year? Certainly by the 40th year in politics.”

From New York Times • Jan. 22, 2021

Thirtieth anniversary of the dissolution of the Soviet Union.

From The Guardian • Dec. 31, 2020

Poots and I were standing at the eastern edge of the Hudson Yards, a twenty-eight-acre tract of real estate that runs from Thirtieth to Thirty-fourth Streets and from Tenth Avenue to the river.

From The New Yorker • Nov. 27, 2016

Her next novel, “The Thirtieth Candle” traced the anxiety of four suburban South African women as they approached their 30th birthdays.

From Washington Times • Dec. 22, 2014

He read some of his poetry, including “In the White Giant’s Thigh,” and “It Was My Thirtieth Year to Heaven.”

From "Bad Boy" by Walter Dean Myers