[{"word":"femtosecond","phonetics":[],"meanings":[{"partOfSpeech":"noun","definitions":[{"definition":"A unit of time equal to 0.000 000 000 000 001 seconds (i.e. 1x10-15 seconds) and with symbol fs.","synonyms":[],"antonyms":[]}],"synonyms":[],"antonyms":[]}],"license":{"name":"CC BY-SA 3.0","url":"https://creativecommons.org/licenses/by-sa/3.0"},"sourceUrls":["https://en.wiktionary.org/wiki/femtosecond"]}]