Standard Lemma guide

attojoule

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.

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noun

Meaning 1

An SI unit of energy, work, and heat equal to 10−18 joules. Symbol: aJ

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

From atto- + joule.

Word forms

Inflections and variants

attojoules — plural

Word family

Derived and related words

Derived: none provided

Related: none provided

Semantic map

Other relationships

Sources

Where this information comes from

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