peritoneum

noun peri·to·ne·um \ ˌper-ə-tə-ˈnē-əm \

Definition of peritoneum

plural peritoneums play \ˌper-ə-tə-ˈnē-əmz\ or peritonea play \ˌper-ə-tə-ˈnē-ə\

: 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

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peritoneal

play \ˌper-ə-tə-ˈnē-əl\ adjective

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peritoneally

play \ˌper-ə-tə-ˈnē-ə-lē\ adverb

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Recent Examples of peritoneum from the Web

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, "HHS secretary readmitted to hospital for further treatment of diverticulitis," 18 Apr. 2018
Lynn told me that her husband, Mark, was diagnosed in September 2016 with late-stage cancer of the peritoneum, or abdominal lining.

— lindsay gellman, Longreads, "The Last Resort," 22 Mar. 2018
Cells can land on the uterosacral ligaments, uterus, fallopian tubes, ovaries, bowels, bladder, peritoneum, appendix, and sometimes in rare cases, the diaphragm, lungs, or the brain.

— meghan cleary, Teen Vogue, "Why Having A Hysterectomy to End Endometriosis Might Not Work," 14 Sep. 2017

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.

Origin and Etymology of 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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First Known Use: 15th century

in the meaning defined above

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Medical Dictionary

peritoneum

noun peri·to·ne·um

variants: or chiefly British peritonaeum play \ˌper-ət-ᵊn-ˈē-əm\

medical Definition of peritoneum

plural peritoneums or chiefly British -naeums play \-ˈē-əmz\ or -nea or chiefly British peritonaea play \-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