Femtosecond
noun ·Rare ·Advanced level
Definitions
- 1 An SI unit of time equal to 10⁻¹⁵ seconds. Symbol: fs
"Holonyms: 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"
- 2 one quadrillionth (10^-15) of a second; one thousandth of a picosecond wordnet
Example
More examples"Holonyms: 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"
Etymology
From femto- + second.
More for "femtosecond"
Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.