retrogress vs fall back

retrogress and fall back both are verbs.

Word	Noun	Adjective	Verb	Adverb
retrogress	No	No	Yes	No
fall back	No	No	Yes	No

As verbs, retrogress and fall back are synonyms defined as:

Other synonyms of retrogress include lapse, recidivate, regress, relapse.

As verbs, fall back is a hyponym of retrogress; that is, fall back is a word with a more specific, narrower meaning than retrogress:

Other hyponyms of retrogress include drop off, fall behind, recede.

retrogress (verb)	fall back (verb)
go back to bad behavior	go back to bad behavior
get worse or fall back to a previous condition	retreat
	hang (back) or fall (behind) in movement, progress, development, etc.
	fall backwards and down
	move back and away from
	have recourse to