Source : Webster's Revised Unabridged Dictionary (1913)

Annelida \An*nel"i*da\, n. pl. [NL. See {Annelid}.] (Zo["o]l.)
   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}.

Chaetopoda \Ch[ae]*top"o*da\, n. pl. [NL., from Gr. ? hair +
   -poda.] (Zo["o]l.)
   A very extensive order of Annelida, 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.