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epicardium vs. pericardium

epicardium
[ep-i-kahr-dee-uhm] / ˌɛp ɪˈkɑr di əm /

noun

Anatomy.
epicardia plural

  1. the inner serous layer of the pericardium, lying directly upon the heart.

pericardium
[per-i-kahr-dee-uhm] / ˌpɛr ɪˈkɑr di əm /

noun

Anatomy.
pericardia plural

  1. the membranous sac enclosing the heart.