plural noun
Si·​pun·​cu·​loi·​dea | \ (ˌ)sīˌpəŋkyəˈlȯidēə \

Definition of Sipunculoidea

1 : a group of marine worms of obscure systematic position that are commonly classed as a division of Gephyrea and that lack setae and have the mouth at the end of a retractile introvert similar to a proboscis and usually provided with tentacles and the anus anterior and dorsal
2 in some classifications
a : a group coextensive with Gephyrea
b : a class or other group comprising Sipunculoidea (see sense 1 above) and Priapuloidea

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History and Etymology for Sipunculoidea

New Latin, from Sipunculus, genus of marine worms (from Latin sipunculus, siphunculus little pipe) + -oidea

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Cite this Entry

“Sipunculoidea.” Dictionary, Merriam-Webster, Accessed 26 Sep. 2020.

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