millionth

American  

[mil-yuhnth] / ˈmɪl yənθ /

adjective

1. coming last in a series of a million.

2. being one of a million equal parts.

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noun

1. the millionth member of a series.

2. a millionth part, especially of one (1/1,000,000).

millionth British  

/ ˈmɪljənθ /

noun

1. 1. one of 1 000 000 approximately equal parts of something

   2. ( as modifier )

      a millionth part

2. one of 1 000 000 equal divisions of a particular scientific quantity

3. the fraction equal to one divided by 1 000 000

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adjective

1. (usually prenominal)

   1. being the ordinal number of 1 000 000 in numbering or counting order, etc

   2. ( as noun )

      the millionth to be manufactured

Etymology

Origin of millionth

First recorded in 1665–75; million + -th ²

Example Sentences

When “Swinging Party,” by the Replacements, came on my shuffle for the millionth time, I knew I had to do something different.

From Slate • Apr. 12, 2026

For scale, a nanometer is one millionth of a millimeter.

From Science Daily • Mar. 4, 2026

This year, Amazon deployed its millionth robot, and treated the fleet to a new data model that improved travel time by 10%.

From Barron's • Nov. 26, 2025

Last weekend, MCU fans, Pascal punks and journalists alike spent their afternoons lambasting the millionth time Pascal has been asked about the “Daddy” title the internet hoisted onto him.

From Salon • Jul. 25, 2025

I’d just picked up the latest Americaman comic to read for the millionth time when it happened—a bright green flash lighting up the sky outside the window.

From "Klawde: Evil Alien Warlord Cat" by Johnny Marciano and Emily Chenoweth