What is the meaning of supplement?

noun

• Textual matter that is added onto a publication; usually at the end.
  • synonyms: addendum, postscript
• A quantity added (e. G. To make up for a deficiency.
  • synonyms: supplementation
• A supplementary component that improves capability.
  • synonyms: accessory, appurtenance, add-on

verb

• Add as a supplement to what seems insufficient.
  • usage: "supplement your diet"
• Serve as a supplement to.
  • usage: "Vitamins supplemented his meager diet"
• Add to the very end.
  • usage: "He appended a glossary to his novel where he used an invented language"
  • synonyms: append, add on, affix