stylomastoid vein vs vena stylomastoidea

stylomastoid vein and vena stylomastoidea both are nouns.

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

As nouns, stylomastoid vein and vena stylomastoidea are synonyms defined as:

stylomastoid vein and vena stylomastoidea: a vein that drains the tympanic cavity and empties into the retromandibular vein

stylomastoid vein (noun)	vena stylomastoidea (noun)
a vein that drains the tympanic cavity and empties into the retromandibular vein	a vein that drains the tympanic cavity and empties into the retromandibular vein