vena stylomastoidea vs vena

vena stylomastoidea and vena both are nouns.

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

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

vena stylomastoidea: a vein that drains the tympanic cavity and empties into the retromandibular vein
vena: a blood vessel that carries blood from the capillaries toward the heart

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

vena stylomastoidea (noun)	vena (noun)
a vein that drains the tympanic cavity and empties into the retromandibular vein	a blood vessel that carries blood from the capillaries toward the heart