Source:http://linkedlifedata.com/resource/umls/id/C0015352
MSH: Interstitial space between cells, occupied by INTERSTITIAL FLUID as well as amorphous and fibrous substances. For organisms with a CELL WALL, the extracellular space includes everything outside of the CELL MEMBRANE including the PERIPLASM and the cell wall.,GO: That part of a multicellular organism outside the cells proper, usually taken to be outside the plasma membranes, and occupied by fluid. [ISBN:0198547684],NCI: Interstitial space between cells, occupied by fluid as well as amorphous and fibrous substances. (On-line Medical Dictionary)