| any of various slender, unsegmented marine worms of the phylum Nemertea, being able to contract and stretch to an extreme extent. |
[ni-mur-tee-uhn] 
| any member of the invertebrate phylum Nemertea, comprising the ribbon worms. |
s name of a Nereid; see -a 2 ) + -an [ni-mur-teen] , adjective | ne·mer·te·an (nĭ-mûr'tē-ən) n. Any of several velvety, usually brightly colored worms of the phylum Nemertina (or Nemertea) that have a flat, unsegmented body with an extensible proboscis and live in the sea or in the mud of the intertidal zone. Also called ribbon worm. adj. Of or belonging to the phylum Nemertina (or Nemertea). [From New Latin Nēmertēs, type genus, from Greek, name of a Nereid.] |
| ribbon worm n. See nemertean. |
ribbon worm
any member of the invertebrate phylum Nemertea (sometimes called Nemertinea, or Rhynchocoela), which includes mainly free-living forms but also a few parasites of crustaceans, mollusks, and sea squirts. The majority of the approximately 900 known nemertean species are found in marine habitats. Some, however, live in freshwater or on land. The name proboscis worm derives from the muscular eversible proboscis, which is housed in a chamber above the gut. This tube-shaped organ, which in many aquatic forms has a needlelike stylet, is typically used to trap the prey; in land-dwelling species it may be used for rapid movement
Learn more about ribbon worm with a free trial on Britannica.com.