| Namespace | MPheno.ontology | Obsolete | false |
| description | any structural anomaly of the serous sac, consisting of mesothelium and a thin external layer of irregular connective tissue, that lines the abdominopelvic cavity and covers most of the viscera contained therein; it forms two sacs: the peritoneal (or greater) sac and the omental bursa (lesser sac) connected by the omental foramen |