Alteration comes from the Latin word alter (the other [of the two]), to Late Latin words alterare  (to change), to Medieval Latin alterationem (nominative alteratio) , to Middle French word alteracion (change/alteration), to Late Middle English alteration.  

The earliest known use of the word alteration in English was in the 14th century (1300s), and the earliest known use of the word alteration in literature was in the Middle English period (1150–1500). The earliest evidence of the word is from a translation by John Trevisa, before 1398.  

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Alteration Definition & Meaning - Merriam-Webster