endocardium

noun

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

Word History

Etymology

New Latin

First Known Use

circa 1864, in the meaning defined above

Time Traveler
The first known use of endocardium was circa 1864

Rhymes for endocardium

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Browse Nearby Words

endocarditis
endocardium
endocarp
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Cite this Entry

“Endocardium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/endocardium. Accessed 30 Jul. 2026.

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Medical Definition

endocardium

noun
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

Britannica.com: Encyclopedia article about endocardium

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