1. an expression of the change or effect produced by the variation in certain variables, or of the ratio between two different quantities. 2. in chemistry, a number or figure put before a chemical formula to indicate how many times the formula is to be multiplied. absorption coefficient absorptivity.
Definition of Alteration. 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 the act of making something different (as e.g. the size of a garment)
c.1300, a movement, a beginning, from shift (v.). This is the word in to make shift make efforts (mid-15c.). Sense of change, alteration is from 1560s. Sense of means to an end is from 1520s; hence an expedient.. Meaning mechanism for changing gear in a motor vehicle is recorded from 1914. Typewriter shift key is from 1893; shift-lock is from 1899.