| noun | a numerical scale used to compare variables with one another or with some reference number |
| noun | 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 |
| noun | a mathematical notation indicating the number of times a quantity is multiplied by itself |
| noun | an alphabetical listing of names and topics along with page numbers where they are discussed |
| noun | the finger next to the thumb |
| verb | list in an index |
| verb | provide with an index “index the book” |
| verb | adjust through indexation “The government indexes wages and prices” |
| index | verb | adjust through indexation |
| exponential | adjective | of or involving exponents |
| indexical | adjective | of or relating to or serving as an index |
| index | noun | an alphabetical listing of names and topics along with page numbers where they are discussed |
| indexer | noun | someone who provides an index |
| indexing | noun | the act of classifying and providing an index in order to make items easier to retrieve |
| indexation | noun | a system of economic regulation: wages and interest are tied to the cost-of-living index in order to reduce the effects of inflation |