/per'i kahr"dee euhm/ , n. , pl. pericardia /-dee euh/ . Anat.
the membranous sac enclosing the heart.
[ 1570-80; perikárdion, n. use of neut. of perikárdios surrounding the heart, equiv. to peri- PERI- + kardios, adj. deriv. of kardía HEART; cf. -CARDIUM ]