vena saphena vs vena

vena saphena and vena both are nouns.

Word	Noun	Adjective	Verb	Adverb
vena saphena	Yes	No	No	No
vena	Yes	No	No	No

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

vena saphena: either of two chief superficial veins of the leg that drain blood from the foot
vena: a blood vessel that carries blood from the capillaries toward the heart

Other hypernyms of vena saphena include vein, venous blood vessel.

vena saphena (noun)	vena (noun)
either of two chief superficial veins of the leg that drain blood from the foot	a blood vessel that carries blood from the capillaries toward the heart