Word Study
endocardium
CIDE DICTIONARY
endocardium, n. [NL., fr. Gr. 'e`ndon within + kardi`a heart.].
The membrane lining the cavities of the heart. [1913 Webster]
OXFORD DICTIONARY
endocardium, n. the lining membrane of the heart.
Etymology
ENDO- + Gk kardia heart
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