ne·​mer·​te·​an ni-ˈmər-tē-ən How to pronounce nemertean (audio)
: any of a phylum (Nemertea synonym Rhynchocoela) of often vividly colored usually long dorsoventrally flattened marine worms that typically burrow in the mud or sand along seacoasts

called also ribbon worm

nemertine adjective or noun

Word History


ultimately from Greek Nēmertēs Nemertes, one of the Nereids

First Known Use

1861, in the meaning defined above

Time Traveler
The first known use of nemertean was in 1861

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Cite this Entry

“Nemertean.” Dictionary, Merriam-Webster, Accessed 4 Feb. 2023.

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