Main Entry: peri·to·ne·um

Variant(s): or chiefly British peri·to·nae·um \ˌper-ət-^ən-ˈē-əm\

Function: noun

Inflected Form(s): plural peri·to·ne·ums or chiefly British peri·to·nae·ums \-ˈē-əmz\ or -nea or chiefly British peri·to·naea \-ˈē-ə\

: the smooth transparent serous membrane that lines the cavity of the abdomen of a mammal, is folded inward over the abdominal and pelvic viscera, and consists of an outer layer closely adherent to the walls of the abdomen and an inner layer that folds to invest the viscera—see parietal peritoneum, visceral peritoneum; compare mesentery 1