noun pl. indexes -·dex′es or indices -·di·ces′ (-di sēz′)

1. index finger
2. a pointer or indicator, as the needle on a dial
3. a thing that points out; indication; sign; representation performance is an index of ability
4. 1. an alphabetical list of names, subjects, etc. together with the page numbers where they appear in the text, usually placed at the end of a book or other publication
   2. thumb index
   3. a list describing the items of a collection and where they may be found; catalog a library index
   4. Index Librorum Prohibitorum
   5. Index Expurgatorius
   6. a periodical that lists books according to subject, with publishing information and summary of contents
5. 1. the relation or ratio of one amount or dimension to another, or the formula expressing this relation cranial index
   2. a number used to measure change in prices, wages, employment, production, etc.: it shows percentage variation from an arbitrary standard, usually 100, representing the status at some earlier time
      in full index number
6. Math.
   1. exponent (sense )
   2. a subscript
   3. an integer or symbol placed above and to the left of a radical ,
7. Printing a sign  calling attention to something; fist

Etymology: L, informer, that which points out < indicare, indicate

transitive verb

1. 1. to make an index of or for
   2. to include in an index
   3. to supply with a thumb index
2. to be an index, or sign, of; indicate
3. to adjust (wages, interest rates, etc.) automatically to changes in the cost of living