regress vs lapse

regress and lapse both are nouns.

Word	Noun	Adjective	Verb	Adverb
regress	Yes	No	Yes	No
lapse	Yes	No	Yes	No

As verbs, regress and lapse are synonyms defined as:

Other synonyms of regress include fall back, recidivate, relapse, retrogress.

As verbs, lapse is a hyponym of regress; that is, lapse is a word with a more specific, narrower meaning than regress:

Other hyponyms of regress include fall back, recidivate, regress, relapse, retrogress, resile, go back, recover, recuperate.

regress (noun)	lapse (noun)
returning to a former state	a mistake resulting from inattention
the reasoning involved when you assume the conclusion is true and reason backward to the evidence	a failure to maintain a higher state
	a break or intermission in the occurrence of something

regress (verb)	lapse (verb)
go back to bad behavior	go back to bad behavior
get worse or fall back to a previous condition	drop to a lower level, as in one's morals or standards
go back to a previous state	end, at least for a long time
go back to a statistical means	for time to move forward
	pass into a specified state or condition; sink into
	let slip