peritoneum

American  

[per-i-tuh-nee-uhm] / ˌpɛr ɪ təˈni əm /

noun

Anatomy.

plural

peritoneums, peritonea

1. the serous membrane lining the abdominal cavity and investing its viscera.

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peritoneum British  

/ ˌpɛrɪtəˈniːəm /

noun

1. a thin translucent serous sac that lines the walls of the abdominal cavity and covers most of the viscera

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peritoneum Scientific  

/ pĕr′ĭ-tn-ē′əm /

plural

peritonea

1. The membrane that lines the walls of the abdomen and the pelvis (called the parietal peritoneum) and encloses the abdominal and pelvic organs (called the visceral peritoneum.) The space between the two, the peritoneal cavity, fills with inflammatory cells and pus when the peritoneum becomes infected.

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Other Word Forms

• peritoneal adjective

Etymology

Origin of peritoneum

First recorded in 1535–45; from Late Latin, variant spelling of peritonaeum, from Greek peritónaion, noun use of neuter of peritónaios, synonymous derivative of perítonos “stretched round”; see peri-, tone, -eous

Example Sentences

Dr Tom Bainton, a consultant gynaecologist specialising in endometriosis at the hospital, said the condition most commonly appears in the pelvis, affecting the ovaries or the peritoneum .

From BBC • Apr. 4, 2026

Furthermore, it’s possible that the constant recirculation of dialysis solution could strain delicate membranes and “burn out the peritoneum faster”, he says.

From Nature • Mar. 10, 2020

Low-grade serous carcinoma of the peritoneum, if we’re being exact.

From Salon • Jul. 9, 2017

Indira died on Monday due to an "acute inflammation of the peritoneum" and was buried after a post-mortem.

From BBC • Jan. 31, 2017

Flaps of fresh sow’s peritoneum ready cut to the proper size came shooting up in little lifts from the Organ Store in the sub-basement.

From "Brave New World" by Aldous Huxley

Related Words

• breast
• heart
• rib cage