ligature vs fastening

ligature and fastening both are nouns.

Word	Noun	Adjective	Verb	Adverb
ligature	Yes	No	No	No
fastening	Yes	No	No	No

As nouns, fastening is a hypernym of ligature; that is, fastening is a word with a broader meaning than ligature:

Other hypernyms of ligature include attachment.

ligature (noun)	fastening (noun)
the act of tying or binding things together	the act of fastening things together
something used to tie or bind	restraint that attaches to something or holds something in place
thread used by surgeons to bind a vessel (as to constrict the flow of blood)
a metal band used to attach a reed to the mouthpiece of a clarinet or saxophone
(music) a group of notes connected by a slur
character consisting of two or more letters combined into one