pyloric vein vs vena gastrica

pyloric vein and vena gastrica both are nouns.

Word	Noun	Adjective	Verb	Adverb
pyloric vein	Yes	No	No	No
vena gastrica	Yes	No	No	No

As nouns, vena gastrica is a hypernym of pyloric vein; that is, vena gastrica is a word with a broader meaning than pyloric vein:

pyloric vein: receives veins from the upper surfaces of the stomach and empties into the portal vein
vena gastrica: one of several veins draining the stomach walls

Other hypernyms of pyloric vein include gastric vein.

pyloric vein (noun)	vena gastrica (noun)
receives veins from the upper surfaces of the stomach and empties into the portal vein	one of several veins draining the stomach walls