vena thyroidea vs thyroid vein

vena thyroidea and thyroid vein both are nouns.

Word	Noun	Adjective	Verb	Adverb
vena thyroidea	Yes	No	No	No
thyroid vein	Yes	No	No	No

As nouns, vena thyroidea and thyroid vein are synonyms defined as:

vena thyroidea and thyroid vein: any of several small veins draining blood from the thyroid area

vena thyroidea (noun)	thyroid vein (noun)
any of several small veins draining blood from the thyroid area	any of several small veins draining blood from the thyroid area