ending vs natural event

ending and natural event both are nouns.

Word	Noun	Adjective	Verb	Adverb
ending	Yes	No	No	No
natural event	Yes	No	No	No

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

Other hypernyms of ending include happening, occurrence, occurrent.

ending (noun)	natural event (noun)
the act of ending something	an event that happens
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