ostium primum

noun
ostium pri·mum | \ -ˈprī-məm \

Medical Definition of ostium primum 

: an opening between the two embryonic atria of the heart that exists temporarily at the bottom of the developing interatrial septum and is eventually closed off by this septum and replaced by the ostium secundum

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Dictionary Entries near ostium primum

ostial

ostitis

ostium

ostium primum

ostium secundum

ostomate

ostomy

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