patching vs fixing

patching and fixing both are nouns.

Word	Noun	Adjective	Verb	Adverb
patching	Yes	No	No	No
fixing	Yes	No	No	No

As nouns, fixing is a hypernym of patching; that is, fixing is a word with a broader meaning than patching:

Other hypernyms of patching include fix, fixture, mend, mending, repair, reparation.

patching (noun)	fixing (noun)
the act of mending a hole in a garment by sewing a patch over it	the act of putting something in working order again
	the sterilization of an animal
	(histology) the preservation and hardening of a tissue sample to retain as nearly as possible the same relations they had in the living body
	restraint that attaches to something or holds something in place