A codicil is a change or addendum to a will that adds new provisions or clarifies a certain portion of the legal document. Here is a brief example that will flesh out the idea of a codicil. Imagine that you just drafted your will and spent quite a bit of money on it. The document was prepared by a licensed attorney, and you took several days thinking through all of the different issues. You decide to leave your home and savings to your son who is living in another city. A week later, you get a disappointing phone call and hear that your son is badly injured in a car accident. You rush to see him and are just in time because he soon passes away. Rather than going through the trouble of writing your entire will over, you add a codicil that takes into account your son's passing.