Definition of nemertean
: 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
nemertineplay \ˈne-mər-ˌtīn\ adjective or noun
Origin and Etymology of nemertean
ultimately from Greek Nēmertēs Nemertes, one of the Nereids
First Known Use: 1861
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