A group of organisms with many cells which are less-specialized than the Metazoa: The rarely used taxon of the animal kingdom, termed Parazoa, was established at one time to contain the phylum Porifera, in distinction from the Eumetazoa containing all other metazoan animals.

A member of the phylum Porifera, the sponges: A parazoon is a multicellular invertebrate that has a body filled with channels and pores which permit water to flow through them and which consist of jelly-like mesohyl inserted between two delicate layers of cells.