peri·​to·​ne·​um | \ ˌper-ə-tə-ˈnē-əm How to pronounce peritoneum (audio) \
plural peritoneums\ ˌper-​ə-​tə-​ˈnē-​əmz How to pronounce peritoneum (audio) \ or peritonea\ ˌper-​ə-​tə-​ˈnē-​ə How to pronounce peritoneum (audio) \

Definition of peritoneum

: the smooth transparent serous membrane that lines the cavity of the abdomen of a mammal and is folded inward over the abdominal and pelvic viscera

Other Words from peritoneum

peritoneal \ ˌper-​ə-​tə-​ˈnē-​əl How to pronounce peritoneum (audio) \ adjective
peritoneally \ ˌper-​ə-​tə-​ˈnē-​ə-​lē How to pronounce peritoneum (audio) \ adverb

Examples of peritoneum in a Sentence

Recent Examples on the Web There are potential complications of peritoneal dialysis, including infection of the peritoneum. Dr. Keith Roach, oregonlive, 9 Feb. 2022 This then would result in the inflammation of your peritoneum, the lining of the insides of your abdomen, called peritonitis, which can be a life-threatening condition and is a surgical emergency. Bruce Y. Lee, Forbes, 31 Jan. 2022 Think of the parietal peritoneum as a membrane corset that wraps around the center of your body and abdomen, says Gregg. Kelly O'mara, Outside Online, 8 May 2020 The current operating theory, though, is that these stitches are caused by irritation of the parietal peritoneum. Kelly O'mara, Outside Online, 8 May 2020 Your abdominal lining, called the peritoneum, has two layers. Ali Nolan, SELF, 6 Dec. 2021 Ovarian cancer may also be in the fallopian tubes, the structures that move your egg from the ovary to your uterus each month, or the peritoneum, the tissue lining that covers organs in your abdomen, the CDC says. Korin Miller,, 15 June 2021 This is the first category because endometriosis often involves the peritoneum as a baseline characteristic. Cassie Shortsleeve, SELF, 25 Sep. 2019 William Schaffner, a professor of medicine and infectious diseases at Vanderbilt University’s medical school, said another possibility is that an infection has spilled into the peritoneum, the lining of the abdomen. Washington Post, 18 Apr. 2018 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'peritoneum.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of peritoneum

15th century, in the meaning defined above

History and Etymology for peritoneum

Middle English, from Late Latin, from Greek peritonaion, neuter of peritonaios stretched around, from peri- + teinein to stretch — more at thin

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The first known use of peritoneum was in the 15th century

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Cite this Entry

“Peritoneum.” Dictionary, Merriam-Webster, Accessed 27 May. 2022.

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More Definitions for peritoneum


variants: or chiefly British peritonaeum \ ˌper-​ət-​ᵊn-​ˈē-​əm How to pronounce peritoneum (audio) \
plural peritoneums or chiefly British peritonaeums\ -​ˈē-​əmz How to pronounce peritoneum (audio) \ or peritonea or chiefly British peritonaea\ -​ˈē-​ə How to pronounce peritoneum (audio) \

Medical Definition of peritoneum

: 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 sense 1

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