fortieth

American  

[fawr-tee-ith] / ˈfɔr ti ɪθ /

adjective

1. next after the thirty-ninth; being the ordinal number for 40.

2. being one of 40 equal parts.

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noun

1. a fortieth part, especially of one (1/40).

2. the fortieth member of a series.

fortieth British  

/ ˈfɔːtɪɪθ /

adjective

1. 1. being the ordinal number of forty in numbering or counting order, position, time, etc. Often written: 40th

   2. ( as noun )

      he was the fortieth

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noun

1. 1. one of 40 approximately equal parts of something

   2. ( as modifier )

      a fortieth part

2. the fraction equal to one divided by 40 ( 1/ 40 )

Etymology

Origin of fortieth

before 1100; Middle English fourtithe, Old English fēowertigotha. See forty, -eth ²

Example Sentences

It orbits extremely close to its star, at a distance just one fortieth that of Mercury from the Sun.

From Science Daily • Mar. 22, 2026

For the past 900 years, the coronation has been held in Westminster Abbey - William the Conqueror was the first monarch to be crowned there, and Charles will be the fortieth.

From BBC • Sep. 18, 2022

The first Sunday in Lent is also called Quadragesima Sunday, which is derived from the Latin words meaning "fortieth," as this first Sunday is exactly 40 days before Easter.

From Fox News • Mar. 6, 2022

Find the fortieth term of a sequence where the first term is −19 and the common difference is seven.

From Textbooks • May 6, 2020

On the fortieth day after the funeral, another church ceremony was held, after which everyone returned to Hurlbut Street.

From "Middlesex: A Novel" by Jeffrey Eugenides