pericardiostomy

noun
peri·​car·​di·​os·​to·​my | \ ˌper-ə-ˌkärd-ē-ˈäs-tə-mē How to pronounce pericardiostomy (audio) \
plural pericardiostomies

Medical Definition of pericardiostomy

: surgical formation of an opening into the pericardium