discontinuation vs ending

discontinuation and ending both are nouns.

Word	Noun	Adjective	Verb	Adverb
discontinuation	Yes	No	No	No
ending	Yes	No	No	No

As nouns, ending is a hypernym of discontinuation; that is, ending is a word with a broader meaning than discontinuation:

discontinuation: the act of discontinuing or breaking off; an interruption (temporary or permanent)
ending: the act of ending something

Other hypernyms of discontinuation include conclusion, termination.

discontinuation (noun)	ending (noun)
the act of discontinuing or breaking off; an interruption (temporary or permanent)	the act of ending something
	the end of a word (a suffix or inflectional ending or final morpheme)
	the last section of a communication
	event whose occurrence ends something
	the point in time at which something ends