split-second

1 of 2

adjective

split-sec·​ond ˈsplit-ˈse-kənd How to pronounce split-second (audio)
Synonyms of split-secondnext
1
: occurring in a split second
a split-second decision
2
: extremely precise
split-second timing

split second

2 of 2

noun

: a fractional part of a second : flash

Examples of split-second in a Sentence

Adjective a day trader who is used to making split-second decisions Noun In a split second, it was all over. a devastating accident can cause everything in your life to change in a split second
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.
Adjective
These guys have to make a split-second decision, and the men and women on our field are incredible. Ryan Morik, FOXNews.com, 5 Feb. 2026 That split-second moment that lives on forever. Greg Echlin, NPR, 4 Feb. 2026
Noun
That kid gets one shot to make that play and make a split second decision against some of the best athletes in the world. Barry Jackson, Miami Herald, 6 Feb. 2026 For a split second, my hearing went numb. Ryan Coleman, Entertainment Weekly, 3 Feb. 2026 See All Example Sentences for split-second

Word History

First Known Use

Adjective

1944, in the meaning defined at sense 1

Noun

1912, in the meaning defined above

Time Traveler
The first known use of split-second was in 1912

Browse Nearby Words

See all Nearby Words

Cite this Entry

“Split-second.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/split-second. Accessed 14 Feb. 2026.

Kids Definition

split second

1 of 2 noun
: a small fraction of a second : flash

split-second

2 of 2 adjective
1
: occurring in a split second
a split-second decision
2
: extremely precise
split-second timing
Last Updated: - Updated example sentences
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