Annelida \An*nel"i*da\, n. pl. [NL. See Annelid.] (Zool.)
   A division of the Articulata, having the body formed of
   numerous rings or annular segments, and without jointed legs.
   The principal subdivisions are the Ch[ae]topoda, including
   the Oligoch[ae]ta or earthworms and Polych[ae]ta or
   marine worms; and the Hirudinea or leeches. See
   Ch[ae]topoda.
   [1913 Webster]

Chaetopoda \Ch[ae]*top"o*da\, n. pl. [NL., from Gr. ? hair +
   -poda.] (Zool.)
   A very extensive order of Annelida (segmented worms),
   characterized by the presence of lateral set[ae], or spines,
   on most or all of the segments. They are divided into two
   principal groups: Oligoch[ae]ta, including the earthworms
   and allied forms, and Polych[ae]ta, including most of the
   marine species.
   [1913 Webster]