zep·​to·​sec·​ond ˈzep-tə-ˌse-kənd How to pronounce zeptosecond (audio)
: 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, 19 Oct. 2020

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'zeptosecond.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1994, in the meaning defined above

Time Traveler
The first known use of zeptosecond was in 1994

Dictionary Entries Near zeptosecond

Cite this Entry

“Zeptosecond.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/zeptosecond. Accessed 26 Sep. 2023.

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