• (n. pl.) Animals without a mouth or regular internal organs, as the sponges.
A·mor`pho·zo'a noun plural [ New Latin , from Greek ... shapeless; 
Amorphozoa is a term applied to some of the lower groups of animals, as the sponges and their allies, which have no regular symmetrical structure.
amorphozoa, amorphozoic Animals without a mouth or regular internal organs; such as, the sponges.