Metazoa
Pronunciation : Met`a*zo"a
Part of Speech : n.
Etymology : [NL., fr. Gr. (Zo?l.)
Definition : Defn: Those animals in which the protoplasmic mass, constituting the egg, is converted into a multitude of cells, which are metamorphosed into the tissues of the body. A central cavity is commonly developed, and the cells around it are at first arranged in two layers, -- the ectoderm and endoderm. The group comprises nearly all animals except the Protozoa.
pl.
Source : Webster's Unabridged Dictionary, 1913