Noun | 1. | phylum Nemertina - proboscis worms animal kingdom, Animalia, kingdom Animalia - taxonomic kingdom comprising all living or extinct animals nemertean, nemertine, proboscis worm, ribbon worm - soft unsegmented marine worms that have a threadlike proboscis and the ability to stretch and contract phylum - (biology) the major taxonomic group of animals and plants; contains classes |