Supplement (album) definition

(1) A supplementary component that improves capability

(2) A quantity added (e.g. to make up for a deficiency)

(3) Textual matter that is added onto a publication; usually at the end

(4) Add to the very end

"He appended a glossary to his novel where he used an invented language"

(5) Add as a supplement to what seems insufficient

"Supplement your diet"

(6) Serve as a supplement to

"Vitamins supplemented his meager diet"