labyrinthine vein vs internal auditory vein

labyrinthine vein and internal auditory vein both are nouns.

Word	Noun	Adjective	Verb	Adverb
labyrinthine vein	Yes	No	No	No
internal auditory vein	Yes	No	No	No

As nouns, labyrinthine vein and internal auditory vein are synonyms defined as:

labyrinthine vein and internal auditory vein: veins that drain the inner ear

labyrinthine vein (noun)	internal auditory vein (noun)
veins that drain the inner ear	veins that drain the inner ear