subclavian vein vs vena subclavia

subclavian vein and vena subclavia both are nouns.

Word	Noun	Adjective	Verb	Adverb
subclavian vein	Yes	No	No	No
vena subclavia	Yes	No	No	No

As nouns, subclavian vein and vena subclavia are synonyms defined as:

subclavian vein and vena subclavia: a continuation of the axillary vein; joins the internal jugular to form the brachiocephalic vein

subclavian vein (noun)	vena subclavia (noun)
a continuation of the axillary vein; joins the internal jugular to form the brachiocephalic vein	a continuation of the axillary vein; joins the internal jugular to form the brachiocephalic vein