millisecond

noun

mil·​li·​sec·​ond ˈmi-lə-ˌse-kənd 

-kənt

: one thousandth of a second

Did you know?

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

If a lion is charging you and milliseconds are the difference between life and death, there’s no time to weigh options. —Julia Daye, Popular Science, 3 Dec. 2025

Penalty shots can reach 80 mph, closing the 12-yard distance in under 250 milliseconds. —Kaif Shaikh, Interesting Engineering, 3 Dec. 2025

That's not a large gap, but every millisecond counts in the world of performance vehicles, and that's enough to earn the Owl Roadster major bragging rights. —New Atlas, 28 Nov. 2025

Unlike fast radio bursts, which are millisecond-long flashes of light with dubious origins, a type II radio burst occurs over minutes, Callingham said. —Ashley Strickland, CNN Money, 16 Nov. 2025

Word History

Etymology

International Scientific Vocabulary

First Known Use

1909, in the meaning defined above

Rhymes for millisecond

• femtosecond
• microsecond
• nanosecond
• picosecond
• beckoned
• reckoned
• second
• seconde

Kids Definition

millisecond

noun

mil·​li·​sec·​ond ˈmil-ə-ˌsek-ənd 

also -ənt

: one thousandth of a second

Medical Definition

millisecond

noun

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

: one thousandth of a second

—abbreviation ms, msec