stirrup vs stapes

stirrup and stapes both are nouns.

Word	Noun	Adjective	Verb	Adverb
stirrup	Yes	No	No	No
stapes	Yes	No	No	No

As nouns, stirrup and stapes are synonyms defined as:

stirrup and stapes: the stirrup-shaped ossicle that transmits sound from the incus to the cochlea

stirrup (noun)	stapes (noun)
support consisting of metal loops into which rider's feet go	the stirrup-shaped ossicle that transmits sound from the incus to the cochlea
the stirrup-shaped ossicle that transmits sound from the incus to the cochlea