is a leech classed as a worm
Leeches are segmented worms in the Subclass Hirudinea that are usually ectoparasitic. They belong to the Class Clitellata (along with earthworms, Subclass Oligochaeta) because of the presence of a clitellum, which is a swelling towards the head of the animal, where the gonads are located.
Leeches. Leech is a common name for over 650 species of largely freshwater, carnivorous worms that comprise the class Hirudinea in the phylum Annelida.