Standard Lemma guide

unionoid

adj · noun · 2 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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Pronunciation

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1

adj

Meaning 1

Relating to, resembling or characteristic of the family Unionidae or its order Unionida of freshwater mussels.

Definition source: English Wiktionary via Wiktextract

Topics: biology, natural-sciences, zoology

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: unionid, unioniform

Antonyms: none provided

2

noun

Meaning 2

Any member of the family Unionidae or its order Unionida of freshwater mussels.

Definition source: English Wiktionary via Wiktextract

Topics: biology, natural-sciences, zoology

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: unioid, unionid

Antonyms: none provided

History

Etymology

From taxonomic name Unio (with insertion of -n- after its etymon, Classical Latin ūniō (stem ūniōn-)) + -oid. Compare earlier unionid and taxonomic name Unionioda.