buttoned vs fastened

buttoned and fastened both are adjectives.

Word	Noun	Adjective	Verb	Adverb
buttoned	No	Yes	No	No
fastened	No	Yes	No	No

As adjectives, buttoned and fastened are synonyms defined as:

buttoned and fastened: furnished or closed with buttons or something buttonlike

buttoned (adjective)	fastened (adjective)
furnished or closed with buttons or something buttonlike	firmly closed or secured
	furnished or closed with buttons or something buttonlike
	fastened with strings or cords