any of a phylum (Annelida) of roundish, wormlike animals having long, segmented bodies, a brain and ventral nerve cord, and a closed circulatory system, including polychaetes, oligochaetes, and leeches
Any of various worms or wormlike animals of the phylum Annelida, characterized by an elongated, cylindrical, segmented body and including the earthworm and leech.