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

It sounds like something from the distant future, but nanotechnology - engineering at a scale of millionths of a millimetre - is already used in lots of everyday real-life tech.

From BBC

A difference of 477 millionths of a second may seem insignificant.

From Science Daily

I have about a millionth of a second where I see it coming before it slams into my glasses and face and the side of my nose like an orange wrecking ball.

From Literature

These little red dots emit much of their light at wavelengths longer than a 10 millionth of a meter, in the mid-infrared.

From Science Daily

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