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

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 Uterine polyps: These are growths that pop up in your endometrium, per the Cleveland Clinic. Korin Miller, SELF, "How Long Does a Period Last, Normally?," 17 May 2018 The leading theory During a woman’s monthly menstrual cycle, hormones signal the endometrium to thicken. Marie Mccullough, Philly.com, "Frustrated endometriosis patients fuel surge in activism while seeking answers," 12 Apr. 2018 In 1989, Sher had published research examining the correlation between the thickness of a woman’s endometrium — the uterine lining — and the successful implantation of an embryo through IVF. 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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Statistics for endometrium

Last Updated

3 Aug 2019

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Time Traveler for endometrium

The first known use of endometrium was circa 1882

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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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not constant or steady

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