coe·lom also ce·lom (sēləm)
n. pl. coeloms or coe·lo·ma·ta (-lə-mätə, -mătə) also ce·loms or ce·loma·ta
The fluid-filled cavity within the body of most multicellular animals, except some invertebrates such as flatworms and cnidarians, that lies between the body wall and the digestive tract and is formed by the splitting of the embryonic mesoderm into two layers. Also called body cavity.
[German Koelom, from Greek koilōma, cavity, from koilos, hollow; see keuə- in the Appendix of Indo-European roots.]
coe·lomic (sĭ-lŏmĭk, -lōmĭk) adj.
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