cufflink vs jewelry

cufflink and jewelry both are nouns.

Word	Noun	Adjective	Verb	Adverb
cufflink	Yes	No	No	No
jewelry	Yes	No	No	No

As nouns, jewelry is a hypernym of cufflink; that is, jewelry is a word with a broader meaning than cufflink:

cufflink: jewelry consisting of one of a pair of linked buttons used to fasten the cuffs of a shirt
jewelry: an adornment (as a bracelet or ring or necklace) made of precious metals and set with gems (or imitation gems)

Other hypernyms of cufflink include jewellery.

cufflink (noun)	jewelry (noun)
jewelry consisting of one of a pair of linked buttons used to fasten the cuffs of a shirt	an adornment (as a bracelet or ring or necklace) made of precious metals and set with gems (or imitation gems)