splenic vein vs vena

splenic vein and vena both are nouns.

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

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

splenic vein: a vein formed by several small veins on the surface of the spleen; joins the superior mesenteric to form the portal vein
vena: a blood vessel that carries blood from the capillaries toward the heart

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

splenic vein (noun)	vena (noun)
a vein formed by several small veins on the surface of the spleen; joins the superior mesenteric to form the portal vein	a blood vessel that carries blood from the capillaries toward the heart