zeptosecond

Z10E1P3T1O1S1E1C3O1N1D2

noun

An SI unit of time equal to 10⁻²¹ seconds. Symbol: zs

“Meronyms: quectosecond < rontosecond < yoctosecond”

Scrabble 25

Meanings

nounzeptosecond (plural zeptoseconds)

plural zeptoseconds

  1. metrologyAn SI unit of time equal to 10⁻²¹ seconds. Symbol: zs

    Meronyms: quectosecond < rontosecond < yoctosecond

    3 more examples

    Holonyms: attosecond < femtosecond < picosecond < nanosecond < microsecond < millisecond < centisecond < decisecond < second < decasecond < minute < hectosecond < kilosecond < hour < day < week < megasecond < fortnight < month < year < gigasecond < century < kiloannum, kiloyear, millennium < terasecond < mega-annum, megayear < petasecond < giga-annum, gigayear < exasecond < zettasecond < yottasecond < ronnasecond < quettasecond

    Hxh son all day any week and any hour any minute any second, any millisecond, any microsecond, any nanosecond any picosecond any femtosecond, any attosecond, any zeptosecond, any yoctosecond, any rontosecond, any quectosecond

    2025 May 23, King Chimera (chimera_4212), X

    sprunker: "ok ill delay the update by 67 years, 67 months, 67 days, 67 hours, 67 seconds, 67 deciseconds, 67 centiseconds, 67 milliseconds, 67 microseconds, 67 nanoseconds, 67 picoseconds, 67 femtoseconds, 67 attoseconds, 67 zeptoseconds, 67 yoctoseconds, 67 rontoseconds, 67 quectoseconds, and 67... plank ^([sic]) time????".

    2025 October 7, baldigaming285, somesillysprunker, “can we all laugh at this guy”, in Reddit, archived from the original on 17 Feb 2026

Origin

Translations

Chinese Mandarin 仄秒
  • 仄秒 (zèmiǎo)10−21 second
Finnish tseptosekunti
  • tseptosekunti10−21 second
Cite this entry
APA

zeptosecond. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/zeptosecond

MLA

“zeptosecond.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/zeptosecond. Accessed November 4, 2026.

Chicago

WatkinsX Dictionary, s.v. “zeptosecond,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/zeptosecond.

Source: zeptosecond on Wiktionary, CC BY-SA 4.0.