Read the dictionary definition of alteration. All definitions for this word.
1. the act of making something different (as e.g. the size of a garment)
2. the act of revising or altering (involving reconsideration and modification)
1. it would require a drastic revision of his opinion
3. an event that occurs when something passes from one state or phase to another
1. the change was intended to increase sales
2. this storm is certainly a change for the worse
3. the neighborhood had undergone few modifications since his last visit years ago