soldering vs fastening

soldering and fastening both are nouns.

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

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

Other hypernyms of soldering include attachment.

soldering (noun)	fastening (noun)
fastening firmly together	the act of fastening things together
	restraint that attaches to something or holds something in place