What is "chaetopoda"

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 (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.