putting to death vs ending

putting to death and ending both are nouns.

Word	Noun	Adjective	Verb	Adverb
putting to death	Yes	No	No	No
ending	Yes	No	No	No

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

Other hypernyms of putting to death include conclusion, termination.

putting to death (noun)	ending (noun)
the act of terminating a life	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