metazoa
  後生動物
  meta·zoa /ˌmɛtəˈzoə/ 名詞 複數
  (單metazoon)後生動物,多細胞動物
  Met·a·zo·a n. pl.  Zool. 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.
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  metazoan
       n : any animal of the subkingdom Metazoa; all animals except
           protozoans and sponges
       [also: metazoa (pl)]
  Metazoa
       n : multicellular animals having cells differentiated into
           tissues and organs and usually a digestive cavity and
           nervous system [syn: subkingdom Metazoa]