improver vs helper

improver and helper both are nouns.

Word	Noun	Adjective	Verb	Adverb
improver	Yes	No	No	No
helper	Yes	No	No	No

As nouns, helper is a hypernym of improver; that is, helper is a word with a broader meaning than improver:

improver: someone devoted to the promotion of human welfare and to social reforms
helper: a person who helps people or institutions (especially with financial help)

Other hypernyms of improver include benefactor.

improver (noun)	helper (noun)
a component that is added to something to improve it	a person who helps people or institutions (especially with financial help)
someone devoted to the promotion of human welfare and to social reforms	a person who contributes to the fulfillment of a need or furtherance of an effort or purpose