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
Any atomic system containing a helium nucleus and an antihelium nucleus.
Definition source: English Wiktionary via Wiktextract
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
History
Etymology tree English helium English onium English -on Proto-Indo-European *-om Proto-Italic *-om Latin -umder. English -ium English -onium English helionium * (helion-antihelion pair): helium + -onium
