"membranous sac which encloses the heart," early 15c., from Medieval Latin pericardium, Latinized form of Greek perikardion "(membrane) around the heart" (Galen), from peri (prep.) "around, about" (see peri-) + kardia "heart" (from PIE root *kerd- "heart"). Related: Pericardiac.
perhaps
peri
peri-
perianth
pericarditis
pericardium
Pericles
pericope
peridot
perigee
perihelion