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

Words nearby thirtieth

Thirteen Colonies, thirteen-lined ground squirrel, thirteenth, Thirteenth Amendment, thirteenth chord, thirtieth, thirty, Thirty days hath September, thirty-eight, thirty-eighth, thirty-fifth

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use thirtieth in a sentence

Another minister arose; a man not yet in his thirtieth year, his form stooped, as beneath the weight of sixty winters.
Alone|Marion Harland
Given at our palace of Hampton Court, the 24th day of July, 1679, and in the one and thirtieth year of our reign.
The Loyalists of America and Their Times, Vol. 1 of 2|Egerton Ryerson
The reference is to the thirtieth chapter of Jeremiah, from which an extract is here made at length.
Messages from the Epistle to the Hebrews|Handley C.G. Moule
He continued to linger till the thirtieth, when he calmly expired, in the sixty-second year of his age.
History of Prince Edward Island|Duncan Campbell

At Thirtieth Street he got off the car and walked west to Silver's place.
From Place to Place|Irvin S. Cobb

British Dictionary definitions for thirtieth

thirtieth

/ (ˈθɜːtɪɪθ) /

adjective

(usually prenominal)

being the ordinal number of thirty in counting order, position, time, etc: often written 30th
(as noun)the thirtieth of the month

noun

one of 30 approximately equal parts of something
(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