Noun.  a marine flatworm that lacks a digestive cavity with definite walls and that receives food into a porous mass endodermal tissue.

This is an unmodified, but possibly outdated, definition from Wiktionary and used here under the Creative Commons license. Wiktionary is a great resource. If you like it too, please donate to Wikimedia.

This entry was last updated on RefTopia from its source on 3/20/2012.