ac·​tin·​o·​branch | \ ak-ˈti-nə-ˌbraŋk\
variants: or actinobranchia \ ¦ak-​tə-​(ˌ)nō-​ˈbraŋ-​kē-​ə \
plural -s

Definition of actinobranch

: a gill-like organ of certain Anthozoa

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First Known Use of actinobranch

circa 1901, in the meaning defined above

History and Etymology for actinobranch

New Latin actinobranchia, from actin- + branchia

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The first known use of actinobranch was circa 1901

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