attosecond

noun

Etymology: Etymology tree English atto- English second English attosecond From atto- + second.

1. An SI unit of time equal to 10⁻¹⁸ seconds. Symbol: as

   “Holonyms: 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”

   “Meronyms: quectosecond < rontosecond < yoctosecond < zeptosecond”