plural noun Ech·i·u·roi·dea \ˌekēyəˈrȯidēə\

Definition of Echiuroidea

  1. :  a group of marine worms of obscure position though commonly classed as a division of Gephyrea and distinguished by a sensitive but nonretractile proboscis overlying the mouth which in some forms (as some worms of the genus Bonellia) may attain great size

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Origin and Etymology of echiuroidea

New Latin, from Echiurus + -oidea

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capable of being understood in two ways

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