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SINCE 1828
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actinostome

noun
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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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Cite this Entry

“Actinostome.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/actinostome. Accessed 23 Feb. 2020.

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