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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.


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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

    1. one of 1000 approximately equal parts of something

    2. ( as modifier )

      a thousandth part

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

    millivolt

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Noun Inflected Forms

Etymology

Origin of thousandth

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

Vocabulary lists containing thousandth

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

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

In the Milky Way, only the central nucleus has star densities remotely comparable, and that region still contains only about one thousandth of the stars needed for the little-red-dot models.

From Science Daily Nov. 29, 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

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

For the thousandth time I realize anew how hard my disease is on her.

From "Everything, Everything" by Nicola Yoon

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

From The Wall Street Journal Dec. 16, 2025

Back then, Britain’s Allan Wells narrowly beat Silvio Leonard in an era when timing didn’t go down into the thousandths of a second.

From Los Angeles Times Aug. 4, 2024

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

Knight won women's individual pursuit by just three thousandths of a second ahead of Germany's Franziska Brausse.

From BBC Jan. 14, 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

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