extremity vs nipper

extremity and nipper both are nouns.

Word	Noun	Adjective	Verb	Adverb
extremity	Yes	No	No	No
nipper	Yes	No	No	No

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

extremity: an external body part that projects from the body
nipper: a grasping structure on the limb of a crustacean or other arthropods

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

extremity (noun)	nipper (noun)
an external body part that projects from the body	a grasping structure on the limb of a crustacean or other arthropods
that part of a limb that is farthest from the torso	a young person of either sex
the outermost or farthest region or point
the greatest or utmost degree
an extreme condition or state (especially of adversity or disease)