vena thoracica vs vena

vena thoracica and vena both are nouns.

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

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

vena thoracica: veins that drain the thoracic walls
vena: a blood vessel that carries blood from the capillaries toward the heart

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

vena thoracica (noun)	vena (noun)
veins that drain the thoracic walls	a blood vessel that carries blood from the capillaries toward the heart