jewellery vs jewelry

jewellery and jewelry both are nouns.

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

As nouns, jewellery and jewelry are synonyms defined as:

jewellery and jewelry: an adornment (as a bracelet or ring or necklace) made of precious metals and set with gems (or imitation gems)

jewellery (noun)	jewelry (noun)
an adornment (as a bracelet or ring or necklace) made of precious metals and set with gems (or imitation gems)	an adornment (as a bracelet or ring or necklace) made of precious metals and set with gems (or imitation gems)