1. an alphabetical list of names, subjects, or topics with page numbers where they can be found in a book
2. a number or ratio that shows changes in prices, costs, or other economic factors
3. the finger next to the thumb

1. to provide a book or document with an index
2. to adjust wages, benefits, or payments according to changes in an economic index

Examples

• Check the index at the back of the book to find information about World War II.
• The consumer price index rose by 2.3% this year.
• She pointed to the map with her index finger.
• The stock market index fell sharply yesterday.
• High unemployment is often an index of economic problems.
• The publisher hired someone to index the textbook.
• Social Security benefits are indexed to inflation.
• Use the index to locate specific topics quickly.