en·​do·​me·​tri·​um | \ ˌen-dō-ˈmē-trē-əm How to pronounce endometrium (audio) \
plural endometria\ ˌen-​dō-​ˈmē-​trē-​əm How to pronounce endometria (audio) \

Definition of endometrium

: the mucous membrane lining the uterus

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Other Words from endometrium

endometrial \ ˌen-​dō-​ˈmē-​trē-​əl How to pronounce endometrial (audio) \ adjective

Examples of endometrium in a Sentence

Recent Examples on the Web The most common form of uterine cancer is endometrial cancer, which starts in the endometrium (the inner lining of the uterus). Katherine Hobson, New York Times, "Know Your Uterus," 18 Apr. 2020 The muscular uterine wall — the myometrium, where cramps take place — is lined with the endometrium, which thickens during the cycle and then is shed during menstruation. Perri Klass, New York Times, "Helping Teenagers With Menstrual Pain," 3 Feb. 2020 Endometrial cancer, which Moore had, takes root in the layer of cells that forms the lining of the uterus, also known as the endometrium. Erika Stallings, SELF, "Why Are Uterine Cancer Rates Rising So Drastically in Black Women?," 6 Nov. 2019 Doctors discovered Fatu had major changes in her endometrium, the inner layer of her uterus. Sheeka Sanahori, USA TODAY, "Poachers forced this rhino subspecies to two. Scientists are in a race to save them.," 22 July 2019 At this point, the general medical consensus is that endometriosis happens when the tissue that lines your uterus (endometrium) begins to grow on other organs. Korin Miller, SELF, "Here’s When to See a Doctor About Period Clots," 1 Mar. 2019 In general, most experts go with the definition shared by the Mayo Clinic, which describes it as a painful disorder in which tissue that normally lines the inside of your uterus (the endometrium) grows outside your uterus. Korin Miller, SELF, "Halsey Is Freezing Her Eggs at Age 23 Due to Her Endometriosis and Previous Miscarriage," 27 Apr. 2018 These nonhormonal early versions probably worked by interfering with ovulation, fertilization, or implantation by causing mild inflammation of the endometrium. Carolyn Todd, Allure, "The History and Evolution of Birth Control in America," 12 July 2018 As women age, the endometrium tends to thin, and the rate of IVF failure increases. Kate Morgan, The Cut, "Viagra’s Other Life as a Female Fertility Aid," 27 Mar. 2018

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

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First Known Use of endometrium

circa 1882, in the meaning defined above

History and Etymology for endometrium

New Latin, from end- + Greek mētra uterus, from mētr-, mētēr mother — more at mother

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Time Traveler for endometrium

Time Traveler

The first known use of endometrium was circa 1882

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Cite this Entry

“Endometrium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/endometrium. Accessed 7 Jul. 2020.

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More Definitions for endometrium


en·​do·​me·​tri·​um | \ -ˈmē-trē-əm How to pronounce endometrium (audio) \
plural endometria\ -​trē-​ə How to pronounce endometria (audio) \

Medical Definition of endometrium

: the mucous membrane lining the uterus that is composed of three layers — see stratum basale, stratum compactum, stratum spongiosum

More from Merriam-Webster on endometrium

Britannica.com: Encyclopedia article about endometrium

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