What is "periproct"

Periproct \Per"i*proct\, n. [Pref. peri- + Gr. ? the anus.] (Zo["o]l.) The region surrounding the anus, particularly of echinoderms.

n. (context zoology English) The region surrounding the anus, particularly in echinoderms.

The periproct is the final body segment in annelid worms. The anus is located on this segment. The term also refers to the small region surrounding the anus of the sea urchin.