A thing added or appended to a document, such as an addition or supplement.
From the latin word 'addendum' meaning something to be added.
- The contract contained a lengthy addendum outlining the specific terms and conditions.
- The addendum to the textbook provided additional information on the topic.
- The author added an addendum to the end of the novel, thanking her fans for their support.
- The addendum to the recipe provided instructions for making a gluten-free version.
- The company issued an addendum to the annual report, clarifying some of the financial data.