SPLIT-SECOND Synonyms: 46 Similar and Opposite Words

split-second 1 of 2

adjective

ˈsplit-ˈse-kənd

Definition of split-second

as in instantaneous

done or occurring without any noticeable lapse in time a day trader who is used to making split-second decisions

Synonyms & Similar Words

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Antonyms & Near Antonyms

split second

2 of 2

noun

as in minute

a very small space of time a devastating accident can cause everything in your life to change in a split second

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

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.

Recent Examples of split-second

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 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

Rispoli seemed not totally aware of what happened in the split seconds before the start of the San Diego Handicap. — Bill Center, San Diego Union-Tribune, 19 July 2026 But the real challenge – and the reason no bird-scale robot has managed this leap before – is the split second in between, when the robot has to shove itself out of the water with nothing but its wings. — New Atlas, 13 July 2026 See All Example Sentences for split-second

Recent Examples of Synonyms for split-second

Adjective

Lauletta and team have ambitions to achieve a rare feat in the sport — building a brand big enough to generate instantaneous recognition beyond the NASCAR bubble.

— Jordan Bianchi, New York Times, 15 Sep. 2026
While the near synchronicity of the worldwide foram flips might seem puzzling, Darling and Ujiié pointed out that what appears instantaneous in the fossil record might unfold over 1,000 years or more in real time.

— Quanta Magazine, Quanta Magazine, 11 Sep. 2026

Definition of instantaneous

Noun

Thirty minutes later, after a physician examined him, he was pronounced dead and covered with a white sheet.

— Arkansas Online, Arkansas Online, 17 Sep. 2026
Set the scene On rugged John’s Island 40 minutes outside of Charleston, Auberge’s Lowcountry debut deftly centers the coastal charm of the South Carolina sea islands—the second most bioactive habitat in the world, after only the Amazon Rainforest.

— Condé Nast, Condé Nast Traveler, 17 Sep. 2026

Definition of minute

Adjective

His bold, unique style was an immediate hit with ad agencies, publications, the corporate world and in pop culture.

— BETH J. HARPAZ THE ASSOCIATED PRESS, Arkansas Online, 18 Sep. 2026
Pressuring currencies One of the most immediate channels through which a tighter Fed policy travels around the world is the dollar.

— Lee Ying Shan, CNBC, 17 Sep. 2026

Definition of immediate

Noun

Like the Series 12, the Ultra 4 can measure your heart rate every five seconds and checks heart rate variability (HRV) 24 times more often than the previous generations.

— Will Greenwald, PC Magazine, 18 Sep. 2026
Please take 15 seconds out of your day to judge for yourself.

— Brittany Allen, Literary Hub, 18 Sep. 2026

Definition of second

Adjective

The patented multi-panel high-rise waistband technology in the leggings boosts muscle memory in core, glutes, and spine for instant alignment, stability, support and pain relief.

— ABC News, ABC News, 14 Sep. 2026
In practice, though, victims of instant-payment fraud often recover little.

— Pawan Jain, The Conversation, 14 Sep. 2026

Definition of instant

Noun

This type of reinforcement can not only disrupt barking at that moment but also decrease unwanted behaviors.

— BestReviews, Chicago Tribune, 18 Sep. 2026
Rather than simply presenting us with the unequal gender dynamics of the times, Biller’s dialogue can’t help but wink at the audience, underlining every moment of misogyny just in case viewers weren’t smart enough to get it themselves.

— Jourdain Searles, HollywoodReporter, 18 Sep. 2026

Definition of moment

Noun

At the same time, consumer expectations have shifted toward authenticity, transparency and inclusive product development — areas where women leaders have historically driven the vision and cultural heartbeat of our industry.

— WWD Staff, Footwear News, 14 Sep. 2026
Big financial pivots still require a human heartbeat and personal judgment.

— Expert Panel®, Forbes.com, 14 Sep. 2026

Definition of heartbeat

Browse Nearby Words

splits

split-second

split second

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Style

“Split-second.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/split-second. Accessed 20 Sep. 2026.

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Synonyms of split-second

adjective

noun

Example Sentences

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