Standard Lemma guide

isomerism

noun · 4 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

the phenomenon of the existence of isomers - the existence of different substances with the same molecular formulae

Definition source: English Wiktionary via Wiktextract

Usage: countable, physical, uncountable

Topics: chemistry, natural-sciences, physical-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

the interconversion of isomers

Definition source: English Wiktionary via Wiktextract

Usage: countable, uncountable

Topics: chemistry, natural-sciences, physical-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

noun

Meaning 3

nuclear isomerism, the phenomenon of the existence of nuclear isomers.

Definition source: English Wiktionary via Wiktextract

Usage: countable, uncountable

Qualifier: nuclear physics

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

4

noun

Meaning 4

the state of being an isomer; the complex of chemical and physical phenomena characteristic of isomers

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

Broader terms: state

History

Etymology

Etymology tree English isomer Proto-Indo-European *-id- Proto-Indo-European *-yéti Proto-Indo-European *-idyéti Proto-Hellenic *-íďďō Ancient Greek -ῐ́ζω (-ĭ́zō) Proto-Indo-European *-mos Proto-Indo-European *-mós Ancient Greek -μός (-mós) Ancient Greek -ισμός (-ismós)der. English -ism English isomerism From isomer + -ism.

Across languages

Translations

18 source translations are retained for this English entry.

  • Bashkir: изомерия (izomeriya) — phenomenon of the existence of isomers
  • Catalan: isomeria — phenomenon of the existence of isomers
  • Chinese Mandarin: 異構 /异构 (yìgòu) — phenomenon of the existence of isomers
  • Czech: izomerie — phenomenon of the existence of isomers
  • Czech: isomerie — phenomenon of the existence of isomers
  • Finnish: isomeria — phenomenon of the existence of isomers
  • French: isomérie — phenomenon of the existence of isomers
  • German: Isomerie — phenomenon of the existence of isomers
  • Irish: isiméireacht — phenomenon of the existence of isomers
  • Italian: isomeria — phenomenon of the existence of isomers
  • Japanese: 異性 (isei) — phenomenon of the existence of isomers
  • Kazakh: изомерия (izomeriä) — phenomenon of the existence of isomers
  • Kyrgyz: изомерия (izomeriya) — phenomenon of the existence of isomers
  • Portuguese: isomeria — phenomenon of the existence of isomers
  • Russian: изомери́я (izomeríja) — phenomenon of the existence of isomers
  • Spanish: isomería — phenomenon of the existence of isomers
  • Swedish: isomeri — phenomenon of the existence of isomers
  • Welsh: isomeredd — phenomenon of the existence of isomers