en·​do·​car·​di·​um ˌen-dō-ˈkär-dē-əm How to pronounce endocardium (audio)
plural endocardia ˌen-dō-ˈkär-dē-ə How to pronounce endocardium (audio)
: a thin serous membrane lining the cavities of the heart

Example Sentences

Recent Examples on the Web One in the outer layer — epicardium — of the heart and the other in the inner layer — endocardium — of the heart. Monica Cull, Discover Magazine, 22 July 2022

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

Word History


New Latin

First Known Use

circa 1864, in the meaning defined above

Time Traveler
The first known use of endocardium was circa 1864

Dictionary Entries Near endocardium

Cite this Entry

“Endocardium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/endocardium. Accessed 30 Jan. 2023.

Medical Definition


en·​do·​car·​di·​um -ˈkärd-ē-əm How to pronounce endocardium (audio)
plural endocardia -ē-ə How to pronounce endocardium (audio)
: a thin serous membrane lining the cavities of the heart

More from Merriam-Webster on endocardium

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