n.
Any member of a phylum (Annelida) of invertebrate animals that possess a body cavity (coelom), movable bristles (setae), and a body divided into segments by crosswise rings.
Known as segmented worms , annelids are divided into three classes: marine worms (Polychaeta; see polychaete ), earthworms (Oligochaeta), and leeches (Hirudinea).