fem·​to·​sec·​ond | \ ˈfem(p)-tə-ˌse-kənd How to pronounce femtosecond (audio) , -kənt, -tō-\

Definition of femtosecond

: one quadrillionth of a second

Examples of femtosecond in a Sentence

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The Non-Lethal Laser-Induced Plasma Effect (NL-LIPE) system can be used to manipulate air molecules, creating a ball of plasma that oscillates to create sound waves with a stream of femtosecond-long laser bursts. Sean Gallagher, Ars Technica, "Non-Lethal Weapon: DOD seeks to use lasers to create shouting will-o-the-wisp," 22 Mar. 2018 Ytterbium is highly stable, so ytterbium atomic clocks are accurate past the nanosecond scale, all the way to the picosecond and femtosecond scale (1/1,000,000,000,000,000th of a second). Avery Thompson, Popular Mechanics, "Here Is the World's Most Stable Atomic Clock," 28 Nov. 2016 Measuring them requires equipment capable of discriminating between femtoseconds. The Economist, "Submarine cables could be repurposed as earthquake detectors," 16 June 2018 Within 30 femtoseconds – millionths of a billionth of a second – the molecule lost more than 50 electrons, far more than expected. Fox News, "Scientists create 'molecular black hole' in laboratory using world's most powerful x-ray beam," 5 June 2017 Computational approaches to protein structure focused on cunning algorithms, rather than on attempting to track atoms femtosecond by femtosecond. Oliver Morton, WIRED, "Gene Machine," 1 July 2001

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'femtosecond.' 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 femtosecond

1976, in the meaning defined above

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The first known use of femtosecond was in 1976

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