index meaning and definition

INDEX noun

Definition of index (noun)

1. a numerical scale used to compare variables with one another or with some reference number
2. 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
   • synonyms: index number, indicant, indicator
3. a mathematical notation indicating the number of times a quantity is multiplied by itself
   • synonyms: exponent, power
4. an alphabetical listing of names and topics along with page numbers where they are discussed
5. the finger next to the thumb
   • synonyms: forefinger, index finger

INDEX verb

Definition of index (verb)

1. list in an index
2. provide with an index
   • "index the book"
3. adjust through indexation
   • "The government indexes wages and prices"