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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ōgənĕs'ŏn
/oʊɡəˈnɛsɒn/
/ˌɒɡəˈnɛsɒn/
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1
noun
Meaning 1
The chemical element (symbol Og) with atomic number 118. It is the heaviest known element. Highly radioactive, it does not occur naturally. Originally expected to be a noble gas, it is now predicted to be a reactive metallic solid, and a semiconductor or a post-transition metal.
Definition source: English Wiktionary via Wiktextract
Usage: uncountable
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
History
Etymology
From Oganessian + -on. Promulgated in June 2016 by IUPAC based on recommendations of the Joint Institute for Nuclear Research and Lawrence Livermore National Laboratory to honor Russian-Armenian physicist Yuri Oganessian (born 1933) who researched superheavy elements. Suffix -on, rather than -ium, is because it is a noble gas (like neon or argon).
Across languages
Translations
33 source translations are retained for this English entry.
Arabic:
أُوغَانِيسُون
(ʔūḡānīsūn)
— chemical element
Armenian:
օգանեսոն
(ōganeson)
— chemical element
Bulgarian:
оганесон
(oganeson)
— chemical element
Catalan:
oganessó
— chemical element
Chinese Mandarin:
鿫
(ào)
— chemical element
Danish:
oganesson
— chemical element
Esperanto:
oganesono
— chemical element
Finnish:
oganesson
— chemical element
French:
oganesson
— chemical element
Georgian:
ოგანესონი
(oganesoni)
— chemical element
German:
Oganesson
— chemical element
Greek:
ογκανέσσιο
(ogkanéssio)
— chemical element
Hungarian:
oganeszon
— chemical element
Icelandic:
oganesson
— chemical element
Irish:
óganasan
— chemical element
Italian:
oganesson
— chemical element
Japanese:
オガネソン
(oganeson)
— chemical element
Kazakh:
оганесон
(oganeson)
— chemical element
Korean:
오가네손
(oganeson)
— chemical element
Latvian:
oganesons
— chemical element
Macedonian:
оганесон
(oganeson)
— chemical element
