Synonyms for Accessory Hemiazygous Vein (same or very similar meaning)
WordNet sense 1 (a vein formed by the union of the 4th to 7th posterior intercostal veins; empties into the azygos vein):
accessory hemiazygos vein, vena hemiazygos accessoriaFrom the ODE community, based on WordNetadd/edit