You are able to change the name of an addition very easily. To do so, access the Payroll tab on the navigation bar and select the "Employee Payroll Setup". Once the employee list page is displayed, click "Edit" to the right of the employees name. This will generate the 'Employee Information', and click "Next" to get on the Additions page of the setup process. 

The list of default additions set up for the company will be displayed. To make changes, simply click in the "Description" box and change the name of the item as needed. When all changes have been made, you will proceed to click "Next", and then "Finish" to update all changes made.