worsening vs falloff

worsening and falloff both are nouns.

Word	Noun	Adjective	Verb	Adverb
worsening	Yes	Yes	No	No
falloff	Yes	No	No	No

As nouns, falloff is a hyponym of worsening; that is, falloff is a word with a more specific, narrower meaning than worsening:

Other hyponyms of worsening include drop-off, falling off, slack, slump.

worsening (noun)	falloff (noun)
changing something with the result that it becomes worse	a noticeable deterioration in performance or quality
process of changing to an inferior state

worsening (adjective)	falloff (adjective)
changing for the worse