| noun | textual matter that is added onto a publication; usually at the end |
| noun | a quantity added (e.g. to make up for a deficiency) |
| noun | a supplementary component that improves capability |
| verb | add as a supplement to what seems insufficient “supplement your diet” |
| verb | serve as a supplement to “Vitamins supplemented his meager diet” |
| verb | add to the very end “He appended a glossary to his novel where he used an invented language” |
| supplement | verb | add to the very end |
| supplementary | adjective | added to complete or make up a deficiency |
| supplemental | adjective | added to complete or make up a deficiency |
| accessory | adjective | furnishing added support |
| accessorial | adjective | nonessential but helpful |
| appurtenant | adjective | furnishing added support |
| appertain | verb | be a part or attribute of |
| add on | verb | add to the very end |
| supplement | noun | a supplementary component that improves capability |
| supplementation | noun | a quantity added (e.g. to make up for a deficiency) |
| appendage | noun | a part that is joined to something larger |
| appendant | adjective | affixed as an appendage |
| add-on | noun | a supplementary component that improves capability |
| affixation | noun | the act of attaching or affixing something |