pseudocelom

pseu·do·ce·lom

(sū'dō-sē'lom),
A partial or false celom, typical of Nematoda (roundworms) and related phyla, in which the body cavity is lined by mesoderm along only one surface (hypodermis, under the cuticular body wall). Compare: celom, acelom.
[pseudo- + G. koilōma, hollow]