split-second

1 of 2

adjective

split-sec·​ond ˈsplit-ˈse-kənd How to pronounce split-second (audio)
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
Kristin Henning, director of the Juvenile Justice Clinic at Georgetown University's law school, said that matters when law enforcement is making a split-second decision. Jade Jackson, IndyStar, 30 Aug. 2025 In a world increasingly dominated by split-second decisions and the relentless pursuit of profit, our survival may depend on defending the value of taking time to think. Luis E. Romero, Forbes.com, 27 Aug. 2025
Noun
The new generation of Volvo Dynamic Steering is designed to detect a front tire puncture and, in a split second, automatically mitigate the impact by assisting the driver to keep the truck on a steady course. Prabhat Ranjan Mishra, Interesting Engineering, 5 Sep. 2025 They’ll be decided in the split second after the click — where expensive, high-intent traffic is either captured or lost. Sindhya Valloppillil, Forbes.com, 19 Aug. 2025 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 7 Sep. 2025.

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
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!