metazoa Meaning, Definition & Usage

  1. noun multicellular animals having cells differentiated into tissues and organs and usually a digestive cavity and nervous system
    subkingdom Metazoa.
  2. noun any animal of the subkingdom Metazoa; all animals except protozoans and sponges
    metazoan.

WordNet

Met`a*zo"a noun plural
Etymology
NL., fr. Gr. after + an animal.
Definitions
  1. (Zoöl.) 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.

Webster 1913