millisecond

noun

mil·​li·​sec·​ond ˈmi-lə-ˌse-kənd How to pronounce millisecond (audio)
-kənt
: one thousandth of a second

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A millisecond isn't long enough for the blink of an eye, but a few milliseconds may determine the winner of a swim race or a hundred-yard dash. With the ever-increasing speed of modern technology, even a millisecond has started to seem a little sluggish; computer operations are now measured in nanoseconds—that is, billionths of a second.

Examples of millisecond in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Such an offering would give institutional investors a leg up in areas of finance like high-frequency trading, where an advantage of a few milliseconds can mean the difference of millions of dollars. — Bobby Allyn, NPR, 1 Aug. 2026 That means no transmitting raw data every millisecond, which is both an energy save and a privacy win, since your data never has to leave the device. — Jackie Snow, IEEE Spectrum, 30 July 2026 The system collects readings every 100 milliseconds from roughly 300 sensors on each machine, using time-series anomaly detection and graph neural networks to detect abnormal operating conditions. — Neetika Walter, Interesting Engineering, 29 July 2026 Running a few milliseconds ahead of such market skinny is money in the bank. — Steve H. Hanke, Fortune, 27 July 2026 See All Example Sentences for millisecond

Word History

Etymology

International Scientific Vocabulary

First Known Use

1909, in the meaning defined above

Time Traveler
The first known use of millisecond was in 1909

Rhymes for millisecond

See All Rhymes for millisecond

Browse Nearby Words

milliroentgen
millisecond
millisite
See all Nearby Words

Cite this Entry

“Millisecond.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/millisecond. Accessed 3 Aug. 2026.

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Kids Definition

millisecond

noun
mil·​li·​sec·​ond ˈmil-ə-ˌsek-ənd How to pronounce millisecond (audio)
also -ənt
: one thousandth of a second

Medical Definition

millisecond

noun
mil·​li·​sec·​ond ˈmil-ə-ˌsek-ənd, -ənt How to pronounce millisecond (audio)
: one thousandth of a second
—abbreviation ms, msec
Last Updated: - Updated example sentences
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