thousandth

American  

[thou-zuhndth, -zuhntth, -zuhnth] / ˈθaʊ zəndθ, -zəntθ, -zənθ /

adjective

1. last in order of a series of a thousand.

2. being one of a thousand equal parts.

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noun

• thousandths
  plural

1. a thousandth part, especially of one (1/1000).

2. the thousandth member of a series.

3. Also thousandth's place (in decimal notation) the position of the third digit to the right of the decimal point.

thousandth British  

/ ˈθaʊzənθ /

adjective

1. (usually prenominal)

   1. being the ordinal number of 1000 in numbering or counting order, position, time, etc

   2. ( as noun )

      the thousandth in succession

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noun

1. 1. one of 1000 approximately equal parts of something

   2. ( as modifier )

      a thousandth part

2. one of 1000 equal divisions of a particular scientific quantity

   millivolt

3. the fraction equal to one divided by 1000 ( 1/ 1000 )

Other Word Forms

Noun Inflected Forms

• thousandths
  plural

Etymology

Origin of thousandth

First recorded in 1545–55; thousand + -th ²

Example Sentences

See Examples For:

thousandth thousandths

Any parent who has read a “Berenstain Bears” book aloud under duress for the thousandth time will know what I mean.

From The Wall Street Journal ● Dec. 12, 2025

He was gifted with a superhuman taste sensitivity: He could easily distinguish a flavor at one ten thousandth of a gram in a fifteen ton batch.

From Salon ● Nov. 7, 2024

A millisecond is a thousandth of a second.

From BBC ● Jul. 22, 2024

The official margin was a thousandth of a second — every bit as close as the Kentucky Derby a day earlier — and Buescher was left both dumbfounded and dejected.

From Seattle Times ● May 5, 2024

Harry moved his aching hand over what felt like the thousandth envelope, writing out Veronica Smethley’s address.

From "Harry Potter And The Chamber Of Secrets" by J. K. Rowling

In some fusion systems, particles hotter than the core of the sun can become unstable within just a few thousandths of a second.

From Science Daily ● Sep. 6, 2026

That yielded speed improvements measured in milliseconds—or thousandths of a second.

From The Wall Street Journal ● Dec. 16, 2025

"It can see things on the scale of a few thousandths of a millimetre," explained Adrian Mancuso, director of physical sciences at Diamond.

From BBC ● Feb. 5, 2025

Because of the simplicity of the 128-bit microchip, the robot runs on a mere 75 nanowatts—a couple thousandths as much power as is consumed by a modern pacemaker.

From Science Magazine ● Mar. 7, 2024

His design called for “a hundred or so pieces,” he explained, “which had to fit together to within a precision of a few thousandths of an inch.”

From "Bomb" by Steve Sheinkin