split-sec·​ond | \ ˈsplit-ˈse-kənd How to pronounce split-second (audio) \

Definition of split-second

 (Entry 1 of 2)

1 : occurring in a split second a split-second decision
2 : extremely precise split-second timing

split second


Definition of split second (Entry 2 of 2)

: a fractional part of a second : flash

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Examples of split-second in a Sentence


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: Noun

In Freedom of Speech, the central figure is not in the middle of speaking but in that split second of thinking and speaking. Brian T. Allen, National Review, "A Closer Look at Rockwell’s Four Freedoms," 22 June 2019 Tennessee guard Jordan Bone's night went from disappointing to life-changing in a split second. Jenna West, SI.com, "Jordan Bone's NBA Draft Party Erupted After He Was Selected in Second Round," 21 June 2019 That code can then be matched against the real thing in a split second when the user touches a scanner, looks at a digital camera or waves a hand. Amy Gamerman, WSJ, "Home Is Where They Know Your Name (and Face, Hands and Fingerprints)," 20 June 2019 For a split second, Ainsley thought Bianca was going to reach out and touch her breasts. Lucinda Rosenfeld, Harper's magazine, "First Daughters," 10 Feb. 2019 The leading hypothesis about the universe’s birth — that a quantum speck of space became energized and inflated in a split second, creating a baby cosmos — solves many puzzles and fits all observations to date. Quanta Magazine, "A New Test for the Leading Big Bang Theory," 11 Sep. 2018 Two men, apparently civilians, were walking into the area just meters from the motorcycles at the moment of the explosion, which a split second later was followed by a second possible blast. Edmund Demarche, Fox News, "Family of suicide bombers killed in attack on Indonesia police headquarters after church bombings," 14 May 2018 In a split second, Cyrus appears wearing a bright purple bob with bangs and the sort of geometric bodycon outfit that pop culture tends to associate with hypothetical future societies. Leah Prinzivalli, Allure, "Miley Cyrus Plays a Version of Herself With Purple Hair in the New Black Mirror Trailer," 15 May 2019 In a split second, her faces morphs from confused to horrified to defeated. Glamour, "Real Women Remember the Horror of Finding Out They Were Paid Less Than Men," 2 Apr. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'split-second.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of split-second


1944, in the meaning defined at sense 1


1912, in the meaning defined above

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Time Traveler for split-second

The first known use of split-second was in 1912

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More Definitions for split-second



English Language Learners Definition of split-second

 (Entry 1 of 2)

: done very quickly
: very accurate or precise

split second


English Language Learners Definition of split second (Entry 2 of 2)

: a very short period of time

More from Merriam-Webster on split-second

Rhyming Dictionary: Words that rhyme with split-second

Thesaurus: All synonyms and antonyms for split-second

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