millionth

American  

[mil-yuhnth] / ˈmɪl jənθ /

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

See Examples For:

millionth

The researchers eventually made progress using electron cryotomography, a high-resolution 3D imaging method capable of revealing structures at the scale of a millionth of a millimeter.

From Science Daily ● Sep. 3, 2026

The founder of sock maker Bombas, David Heath, got a tattoo—of the Bombas logo and its motto—after the company donated its millionth pair of socks.

From The Wall Street Journal ● Jul. 31, 2026

Schiller calls the move “a half-desperate plan to simply change the background scenery of my life for the millionth time.”

From Los Angeles Times ● Jul. 20, 2026

The one millionth parkrun has taken place at Bushy Park in south west London, where the community event's founder praised "the benefit and the joy of taking part".

From BBC ● Jun. 13, 2026

Quantum mechanics, on the other hand, deals with phenomena on extremely small scales, such as a millionth of a millionth of an inch.

From "A Brief History of Time: And Other Essays" by Stephen Hawking