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

Synonyms of split-second

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Adjective

Noun

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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
Late decision costs Twins A split-second decision by Lewis on an unfamiliar play hastened the end of Saturday’s game. — Dan Hayes, New York Times, 2 Aug. 2026 Trump’s Truth Social is launching a premium ‘Truth API’ that sells Wall Street traders split-second early access to his market-moving posts, stoking new criticisms of insider trading and self-enrichment in the Oval Office. — Bernard Condon, Los Angeles Times, 2 Aug. 2026
Noun
Davis even squared up at Chase for a split second before cooler heads prevailed. — Ryan Morik, FOXNews.com, 30 July 2026 The moment the ride paused at the top — the very split second of anticipation before the drop — was equally fantastic, and worth a return trip. — Reeti Malhotra, Sacbee.com, 24 July 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

Rhymes for split-second

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Browse Nearby Words

split screen
split-second
split second
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Cite this Entry

“Split-second.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/split-second. Accessed 10 Aug. 2026.

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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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