zep·​to·​sec·​ond | \ ˈzep-tə-ˌse-kənd How to pronounce zeptosecond (audio) , -kənt \

Definition of zeptosecond

: one sextillionth of a second

Examples of zeptosecond in a Sentence

Recent Examples on the Web The ultra-quick journey took 247 zeptoseconds, according to a team of German researchers, with a zeptosecond representing a trillionth of a billionth of a second. NBC News, "Scientists clock the fastest interval of time in 'zeptoseconds'," 19 Oct. 2020

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

First Known Use of zeptosecond

1994, in the meaning defined above

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The first known use of zeptosecond was in 1994

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Cite this Entry

“Zeptosecond.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/zeptosecond. Accessed 20 Apr. 2021.

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