#improver__addition  a component that is added to something to improve it; "the addition of a bathroom was a major improvement"; "the addition of cinammon improved the flavor"
  supertype:  component__constituent  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"
  subtype:  additive  something added to enhance food or gasoline or paint or medicine
     subtype:  adjuvant  an additive that enhances the effectiveness of medical treatment
     subtype:  food_additive__artificial_additive  an additive to food intended to improve its flavor or appearance or shelf-life
  subtype:  afterthought  an addition that was not included in the original plan; "the garage was an afterthought"
  subtype:  annex__annexe__extension__wing  an addition that extends a main building
     subtype:  ell  an extension at the end and at right angles to the main building
  subtype:  attachment.improver  a supplementary part or accessory
  subtype:  elongation.improver__extension  an addition to the length of something

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