mil·​li·​sec·​ond | \ˈmi-lə-ˌse-kənd, -kənt\

Definition of millisecond 

: 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

Even if the differences cancel each other out on the scale of seconds or minutes, small fluctuations could make the clock less effective on a millisecond or nanosecond scale. Avery Thompson, Popular Mechanics, "Here Is the World's Most Stable Atomic Clock," 28 Nov. 2016 In fact, days are lengthening by only 1.8 milliseconds a century, said Stephen Meyers, a geoscientist at the University of Wisconsin and a co-author of the study. Denise Chow /, NBC News, "Days on Earth are getting longer, but don't get too excited," 26 June 2018 Some professional investors make a virtue of incessant trading, with a holding period for shares of milliseconds rather than years. The Economist, "Technology can tackle investors’ flaws," 26 Apr. 2018 Some might wonder why there is no manual or dual-clutch option, but don't be alarmed or complain; the ZF 'box is probably the best automatic gearbox available today and will change gears in less than 100 milliseconds. Jonathan M. Gitlin, Ars Technica, "The Alfa Romeo Giulia Ti: A sports sedan for people who want to drive," 6 Apr. 2018 The shocks’ stiffness and damping can change every millisecond. Mark Phelan, Detroit Free Press, "2019 Ford Raptor adds adaptive shocks ready for 'jump mode'," 24 May 2018 Others were much broader, stretching out to a millisecond, and a few appeared to contain multiple overlapping peaks. John Timmer, Ars Technica, "Whatever causes fast radio bursts is sitting in an intense magnetic field," 15 Jan. 2018 In contrast, the N.T.P. standard can synchronize computers no more accurately than a millisecond, or one thousandth of a second. John Markoff, New York Times, "Time Split to the Nanosecond Is Precisely What Wall Street Wants," 29 June 2018 Kemp sprinted home from first base, placing his hand on home plate a millisecond before Jonathan Lucroy's tag. Chandler Rome, Houston Chronicle, "Astros sweep Athletics, extend winning streak to 8," 15 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'millisecond.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of millisecond

1909, in the meaning defined above

History and Etymology for millisecond

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Last Updated

24 Oct 2018

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The first known use of millisecond was in 1909

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English Language Learners Definition of millisecond

: one thousandth of a second


mil·​li·​sec·​ond | \ˈmil-ə-ˌsek-ənd, -ənt \

Medical Definition of millisecond 

: one thousandth of a second abbreviation ms, msec

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What made you want to look up millisecond? Please tell us where you read or heard it (including the quote, if possible).


something that serves to warn or remind

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