'Endocardium' definitions:

Definition of 'endocardium'

From: WordNet
noun
The membrane that lines the cavities of the heart and forms part of the heart valves

Definition of 'Endocardium'

From: GCIDE
  • Endocardium \En`do*car"di*um\, n. [NL., fr. Gr. 'e`ndon within + kardi`a heart.] (Anat.) The membrane lining the cavities of the heart. [1913 Webster]