backslider vs recidivist

backslider and recidivist both are nouns.

Word	Noun	Adjective	Verb	Adverb
backslider	Yes	No	No	No
recidivist	Yes	No	No	No

As nouns, backslider and recidivist are synonyms defined as:

backslider and recidivist: someone who lapses into previous undesirable patterns of behavior

Other synonyms of backslider include reversionist.

backslider (noun)	recidivist (noun)
someone who lapses into previous undesirable patterns of behavior	someone who lapses into previous undesirable patterns of behavior
	someone who is repeatedly arrested for criminal behavior (especially for the same criminal behavior)