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
Poorer sleep and longer shifts were associated with reduced cognitive function, which can affect a firefighter’s ability to make split-second calls, such as when to retreat from an escalating fire. — Julian L. Gallegos, The Conversation, 27 Aug. 2026 Most finishes of this kind are reactive, split-second adjustments, whereas Ballard appears to telegraph the strike long before the ball reaches him. — Conor O'Neill, New York Times, 23 Aug. 2026
Noun
In the days leading up to Saturday’s game against the Saints, Bennett and Simpson split second-team reps during the teams’ joint practice. — Los Angeles Times, 22 Aug. 2026 Rodriguez turning his brain off for a split second in a game that was long, long over is somewhat forgivable. — Mark Harris Outkick, FOXNews.com, 19 Aug. 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 1 Sep. 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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