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actinostome

noun
ac·​tin·​o·​stome | \ ak-ˈti-nə-ˌstōm\
plural -s

Definition of actinostome

1 : the mouth of a radially symmetrical animal
2 : the peristome of an echinoderm

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First Known Use of actinostome

1860, in the meaning defined at sense 1

History and Etymology for actinostome

actin- + -stome

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The first known use of actinostome was in 1860

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