The noun index has 5 senses (first 2 from tagged texts)
1. (1) index -- (a numerical scale used to compare variables with one another or with some reference number)
2. (1) index, index number, indicant, indicator -- (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)
3. exponent, power, index -- (a mathematical notation indicating the number of times a quantity is multiplied by itself)
4. index -- (an alphabetical listing of names and topics along with page numbers where they are discussed)
5. index, index finger, forefinger -- (the finger next to the thumb)
Overview of verb index
The verb index has 3 senses (first 1 from tagged texts)
1. (1) index -- (list in an index)
2. index -- (provide with an index; "index the book")
3. index -- (adjust through indexation; "The government indexes wages and prices")