Definition of: nemertean

(ni·mûr′tē·ən) noun
One of a phylum or class (Nemertea) of flatworms, mostly marine and non-parasitic, with skin ciliated, proboscis retractile, and muscular, vascular, and nervous systems characteristically developed: often brilliantly colored.
—adjective Of or pertaining to the Nemertea. [<NL <Gk. Nēmertēs, one of the Nereids]
—ne·mer′ti·an, ne·mer′tine, ne′mer·tin′e·an adjective & noun