(a numerical scale used to compare variables with one another or with some reference number) index
(a number or ratio (a value on a scale of measurement) derived from a series of observed facts; can reveal relative changes as a function of time) index number; indicant; indicator; index
(a mathematical notation indicating the number of times a quantity is multiplied by itself) exponent; power; index
(an alphabetical listing of names and topics along with page numbers where they are discussed) index