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
Scammers count on that split-second panic. — Kurt Knutsson, FOXNews.com, 17 June 2026 That still gives drivers access to navigation and calls through buttons on the wheel or dash without the split-second reach that can lead to a crash. — Gabby Sartori, USA Today, 5 June 2026
Noun
Then, in a split second, his fly is gone, yanked into the depths by a rainbow. — Dac Collins, Outdoor Life, 1 July 2026 For a split second, these guys are laughing and having a good time despite what’s to come. — Brayden Garcia, Fort Worth Star-Telegram, 5 June 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

See All Rhymes for split-second

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 7 Jul. 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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