venae esophageae vs oesophageal veins

venae esophageae and oesophageal veins both are nouns.

Word	Noun	Adjective	Verb	Adverb
venae esophageae	Yes	No	No	No
oesophageal veins	Yes	No	No	No

As nouns, venae esophageae and oesophageal veins are synonyms defined as:

venae esophageae and oesophageal veins: small veins from the esophagus emptying into the brachiocephalic vein or the azygos veins

Other synonyms of venae esophageae include esophageal veins.

venae esophageae (noun)	oesophageal veins (noun)
small veins from the esophagus emptying into the brachiocephalic vein or the azygos veins	small veins from the esophagus emptying into the brachiocephalic vein or the azygos veins