thirteenth

American  

[thur-teenth] / ˈθɜrˈtinθ /

adjective

1. next after the twelfth; being the ordinal number for 13.

2. being one of 13 equal parts.

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noun

1. a thirteenth part, especially of one (1/13).

2. the thirteenth member of a series.

thirteenth British  

/ ˈθɜːˈtiːnθ /

adjective

1. (usually prenominal)

   1. coming after the twelfth in numbering or counting order, position, time, etc; being the ordinal number of thirteen: often written 13th

   2. ( as noun )

      Friday the thirteenth

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noun

1. 1. one of 13 equal or nearly equal parts of something

   2. ( as modifier )

      a thirteenth part

2. the fraction equal to one divided by 13 ( 1/ 13 )

3. music

   1. an interval of one octave plus a sixth See also interval

   2. short for thirteenth chord

Etymology

Origin of thirteenth

before 900; thirteen + -th ²; replacing Middle English thrittenthe ( three, tenth ), Old English thryttēotha ( tithe )

Example Sentences

The filing argues the judge "acted as a thirteenth juror" in the case and calls the sentence "draconian".

From BBC • Dec. 24, 2025

The authors of the Speculum paper write that this identification was a mistaken one, the result of a misreading, in the thirteenth century, of an account of the giant written in Latin.

From Science Daily • Mar. 25, 2024

The rescuers saw their hopes dashed on the thirteenth day of the operation, when their drilling machine broke down beyond repair.

From Seattle Times • Nov. 28, 2023

No date has been set for a thirteenth attempt to elect a president.

From Washington Times • Jun. 14, 2023

As it happens, this is the first occasion since the establishment of universities in the thirteenth century on which a philosophical theory was destroyed by a fact.

From "The Invention of Science" by David Wootton