Standard Lemma guide

femtogram

noun · 1 senses · updated from the 2026-07-25 local source snapshot

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.

Sound

Pronunciation

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1

noun

Meaning 1

An SI unit of mass equal to 10−15 grams. Symbol: fg

Definition source: English Wiktionary via Wiktextract

Topics: metrology

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

History

Etymology

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 gram English femtogram From femto- + gram.

Across languages

Translations

3 source translations are retained for this English entry.

  • Finnish: femtogramma — unit of mass
  • Spanish: femtogramo — unit of mass
  • Swedish: femtogram — unit of mass