Improver

Im`prov´er

n.

1.

One who, or that which, improves.

Thesaurus

Noun	1.	improver - someone devoted to the promotion of human welfare and to social reforms do-gooder, humanitarian benefactor, helper - a person who helps people or institutions (especially with financial help)
	2.	improver - a component that is added to something to improve it; "the addition of a bathroom was a major improvement"; "the addition of cinnamon improved the flavor" add-on, addition additive - something added to enhance food or gasoline or paint or medicine afterthought - an addition that was not included in the original plan; "the garage was an afterthought" annex, annexe, wing, extension - an addition that extends a main building attachment - a supplementary part or accessory constituent, element, component - an artifact that is one of the individual parts of which a composite entity is made up; especially a part that can be separated from or attached to a system; "spare components for cars"; "a component or constituent element of a system" elongation, extension - an addition to the length of something