To delete a menu item go to the menu Tools > User Defined Data > Category.
Click on the delete icon ( 
) in the corresponding line of the menu item you wish to delete. The system will ask for confirmation before deleting to ensure an accidental delete does not occur.
To continue with the deletion click on the OK button or press the CANCEL button to exit out of the delete process.
A message will appear once you have concluded deleting the item.