bronchial vein vs vena

bronchial vein and vena both are nouns.

Word	Noun	Adjective	Verb	Adverb
bronchial vein	Yes	No	No	No
vena	Yes	No	No	No

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

bronchial vein: veins serving the bronchi; empty into the azygos vein
vena: a blood vessel that carries blood from the capillaries toward the heart

Other hypernyms of bronchial vein include vein, venous blood vessel.

bronchial vein (noun)	vena (noun)
veins serving the bronchi; empty into the azygos vein	a blood vessel that carries blood from the capillaries toward the heart