Metazoa

n. division of multi-celled animals (Zoology)

Animals are a major group of multicellular organisms, of the kingdom Animalia or Metazoa. Their body plan becomes fixed as they develop, usually early on in their development as embryos, although some undergo a process of metamorphosis later on in their life. Most animals are motile - can move spontaneously and independently.
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Noun
1. multicellular animals having cells differentiated into tissues and organs and usually a digestive cavity and nervous system
(synonym) subkingdom Metazoa
(hypernym) subkingdom
(member-holonym) Animalia, kingdom Animalia, animal kingdom
(member-meronym) metazoan

(n. pl.)
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.
  

A major division in the Animal Kingdom consisting of multicellular animals.