Source : Webster's Revised Unabridged Dictionary (1913)

Spiodea \Spi*o"de*a\, n. pl. [NL., fr. Spio the typical genus.]
   (Zo["o]l.)
   An extensive division of marine Annelida, including those
   that are without oral tentacles or cirri, and have the gills,
   when present, mostly arranged along the sides of the body.
   They generally live in burrows or tubes.