Term Name:	aortic sac
Synonyms:	saccus aorticus
Definition:	The dilated structure that is lined by endothelial cells and located at the arterial pole of the heart just above (distal to) the truncus arteriosus in mammalian embryos; it is the primordial vascular channel from which the aortic arches (and eventually the dorsal aortae) arise; the aortic sac is homologous to the ventral aorta of gill-bearing vertebrates
Ontology:	Cell Ontology [UBERON:0005432]