appendage vs parapodium

appendage and parapodium both are nouns.

Word	Noun	Adjective	Verb	Adverb
appendage	Yes	No	No	No
parapodium	Yes	No	No	No

As nouns, parapodium is a hyponym of appendage; that is, parapodium is a word with a more specific, narrower meaning than appendage:

appendage: an external body part that projects from the body
parapodium: one of a pair of fleshy appendages of a polychete annelid that functions in locomotion and breathing

Other hyponyms of appendage include chelicera, mouthpart, fang, chela, claw, nipper, pincer, fin, pleopod, swimmeret, limb, dactyl, digit.

appendage (noun)	parapodium (noun)
a part that is joined to something larger	one of a pair of fleshy appendages of a polychete annelid that functions in locomotion and breathing
an external body part that projects from the body
a natural prolongation or projection from a part of an organism either animal or plant