Standard Lemma guide
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
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noun
An SI unit of energy, work, and heat equal to 10−15 joules. Symbol: fJ
Definition source: English Wiktionary via Wiktextract
Topics: metrology
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
History
Etymology tree Proto-Indo-European *pénkwe Proto-Germanic *fimf Proto-Indo-European *déḱm̥ Proto-Germanic *tehun Proto-Germanic *fimftehun Old Norse fimmtánder. Danish femtender. English femto- English joule English femtojoule From femto- + joule.
