pseudocoelom
noun
pseu·do·coe·lom ˌsü-də-ˈsē-ləm 
variants or pseudocoel
ˈsü-də-ˌsēl
plural pseudocoeloms or pseudocoels
: a body cavity that is not a product of gastrulation and is not lined with a well-defined mesodermal membrane
Word History
First Known Use
1863, in the meaning defined above
Medical Definition
pseudocoelom
noun
pseu·do·coe·lom ˌsüd-ə-ˈsē-ləm
variants or pseudocoel also pseudocele or pseudocoele
ˈsüd-ō-ˌsēl
: a body cavity (as in various worms) that is not the product of gastrulation and is not lined with a well-defined mesodermal membrane