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