Term: ball common cardinal vein
Name: ball
Synonyms: yolk ball
Definition: The anterior round region of the yolk cell present after the yolk extension forms during the segmentation period.
Ontology: Anatomy Ontology [ZFA:0000006]

Name: common cardinal vein
Synonyms: duct of Cuvier
Definition: Bilaterally paired longitudinal vein; the anterior cardinal returns blood from the head, and the posterior cardinal returns it from the trunk; these two vessels join together on each side as the common cardinal vein (duct of Cuvier; misnamed the vitelline vein) that leads across the yolk cell to the heart's sinus venosus.
Ontology: Anatomy Ontology [ZFA:0000186]