fag end vs ending

fag end and ending both are nouns.

Word	Noun	Adjective	Verb	Adverb
fag end	Yes	No	No	No
ending	Yes	No	No	No

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

Other hypernyms of fag end include end.

fag end (noun)	ending (noun)
the frayed end of a length of cloth or rope	the act of ending something
the time of the last part of 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