An amendment is a formal alteration to any official document or record, typically with the aim of improving it for the better. This alteration may take many forms, not only the addition of material (such as, for example the 19th Amendment of the Constitution of the United States of America which grants voting rights to women) but also removal of excess, invalid or outdated text.
An amendment may also be made to soil, such as with manure, for improving the nutrient content.