metazoan adjective 2noun 2forms 2 adjective2 •Having to do with animals that are multicellular. •Having to do with animals that develop from an embryo with three tissue layers. noun2 •Any animal that is multicellular. •(no longer used) Any animal that undergoes development from an embryo stage with two or three tissue layers, namely the ectoderm, endoderm, and sometimes mesoderm. formsmetazoa · metazoans
