ep·i·car·di·um 
(ĕp′ĭ-kärdē-əm)
(ĕp′ĭ-kärdē-əm)n. pl. ep·i·car·di·a (-dē-ə)
The inner layer of the pericardium that is in actual contact with the surface of the heart.
[New Latin : EPI- + Greek kardiā, heart; see kerd- in the Appendix of Indo-European roots.]
ep′i·cardi·al adj.