accompanying vein vs vena

accompanying vein and vena both are nouns.

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

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

accompanying vein: a vein accompanying another structure; a vein may accompany an artery in such a way that the arterial pulses aid venous return
vena: a blood vessel that carries blood from the capillaries toward the heart

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

accompanying vein (noun)	vena (noun)
a vein accompanying another structure; a vein may accompany an artery in such a way that the arterial pulses aid venous return	a blood vessel that carries blood from the capillaries toward the heart