alter [LME] If you alter something you change it to something else. The word comes via French from Latin alter ‘other’, also found in alternative [M16th]. It also lies behind altruism [M19th] which is from French altrui ‘somebody else’, from Latin alteri huic ‘to this other’. The French term was coined by the founder of sociology, Auguste Comte (1798–1857), on the pattern of egotism.