"Minor alterations" refers to small changes or adjustments made to something. These changes are usually not significant or drastic, but rather small and inconspicuous modifications.
I followed her recipe almost exactly, with just a few minor alterations when it came to the additions. (butterlustblog.com)
Parenting Plans can be difficult to change - judges usually don't like to be bothered to make minor alterations in an existing Parenting Plan. (parentingplan.net)
I only had to get minor alterations done in the chest area and at the hem. (bhldn.com)