do-gooder vs improver

do-gooder and improver both are nouns.

Word	Noun	Adjective	Verb	Adverb
do-gooder	Yes	No	No	No
improver	Yes	No	No	No

As nouns, do-gooder and improver are synonyms defined as:

do-gooder and improver: someone devoted to the promotion of human welfare and to social reforms

Other synonyms of do-gooder include humanitarian.

do-gooder (noun)	improver (noun)
someone devoted to the promotion of human welfare and to social reforms	a component that is added to something to improve it
	someone devoted to the promotion of human welfare and to social reforms