index

[ in-deks ]
See synonyms for: indexindexedindices on Thesaurus.com

noun,plural in·dex·es, in·di·ces [in-duh-seez]. /ˈɪn dəˌsiz/.
  1. (in a nonfiction book, monograph, etc.) a more or less detailed alphabetical listing of names, places, and topics along with the numbers of the pages on which they are mentioned or discussed, usually included in or constituting the back matter.

  2. a sequential arrangement of material, especially in alphabetical or numerical order.

  1. something used or serving to point out; a sign, token, or indication: a true index of his character.

  2. something that directs attention to some fact, condition, etc.; a guiding principle.

  3. a pointer or indicator in a scientific instrument.

  4. a piece of wood, metal, or the like, serving as a pointer or indicator.

  5. Digital Technology.

    • a value that identifies and is used to locate a particular element within a data array or table.

    • a reference table that contains the keys or references needed to address data items.

    • the part of a search engine where website addresses are cataloged with their associated keywords in order to quickly retrieve the most relevant web pages when a user submits a search query.

  6. Also called fist, hand .Printing. a sign in the shape of a hand with extended index finger, used to point out a particular note, paragraph, etc.

  7. a light, smooth cardboard stock.

  8. the forefinger.

  9. a number or formula expressing some property, ratio, etc., of something indicated: index of growth; index of intelligence.

  10. Statistics. index number.

  11. Economics. price index.

  12. Algebra.

    • an exponent.

    • the integer n in a radical  defining the n-th root: ∛ is a radical having index three.

    • a subscript or superscript indicating the position of an object in a series of similar objects, as the subscripts 1, 2, and 3 in the series x1, x2, x3.

  13. Horology. a leverlike regulator for a hairspring.

  14. (initial capital letter)Roman Catholic Church.

  15. (usually initial capital letter) any list of forbidden or otherwise restricted material deemed morally or politically harmful by authorities: an Index of disapproved books relating to Communism.

  16. Obsolete.

    • a table of contents.

    • a preface or prologue.

verb (used with object)
  1. to provide with an index, as a book.

  2. to enter in an index, as a name or topic.

  1. to serve to indicate: warm breezes indexing the approach of spring.

  2. to place (a book) on an official list as politically or morally harmful: The commissar insisted on indexing the book.

  3. to rotate (work) on a milling machine in order to repeat the milling operation at a new position.

  4. Economics. to adjust (wages, taxes, etc.) automatically according to changes in the cost-of-living level or another economic indicator, especially to offset inflation.

  5. Digital Technology. (of a search engine) to catalog (a website) using keywords: Search engines use automated algorithms to index billions of web pages, but that still accounts for only a fraction of the content on the internet.

Origin of index

1
First recorded in 1350–1400; Middle English, from Latin: “informer, pointer,” equivalent to in-in-2 + -dec- (combining form of dic-, “show, declare, indicate,” akin to teach;see indicate) + -s nominative singular ending;

Other words from index

  • in·dex·a·ble, adjective
  • in·dex·er, noun
  • in·dex·i·cal, adjective
  • in·dex·i·cal·ly, adverb
  • in·dex·less, adjective
  • non·in·dexed, adjective
  • o·ver·in·dex, verb (used with object)
  • o·ver·in·dex·ing, noun
  • re·in·dex, verb (used with object)
  • un·in·dexed, adjective
  • well-indexed, adjective

Words that may be confused with index

Words Nearby index

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use index in a sentence

British Dictionary definitions for index

index

/ (ˈɪndɛks) /


nounplural -dexes or -dices (-dɪˌsiːz)
  1. an alphabetical list of persons, places, subjects, etc, mentioned in the text of a printed work, usually at the back, and indicating where in the work they are referred to

  1. library science a systematic list of book titles or author's names, giving cross-references and the location of each book; catalogue

  2. an indication, sign, or token

  3. a pointer, needle, or other indicator, as on an instrument

  4. maths

    • another name for exponent (def. 4)

    • a number or variable placed as a superscript to the left of a radical sign indicating by its value the root to be extracted, as in ³√8 = 2

    • a subscript or superscript to the right of a variable to express a set of variables, as in using x i for x 1, x 2, x 3, etc

  5. a numerical scale by means of which variables, such as levels of the cost of living, can be compared with each other or with some base number

  6. a number or ratio indicating a specific characteristic, property, etc: refractive index

  7. Also called: fist a printer's mark (☛) used to indicate notes, paragraphs, etc

  8. obsolete a table of contents or preface

verb(tr)
  1. to put an index in (a book)

  2. to enter (a word, item, etc) in an index

  1. to point out; indicate

  2. to index-link

  3. to move (a machine or a workpiece held in a machine tool) so that one particular operation will be repeated at certain defined intervals

Origin of index

1
C16: from Latin: pointer, hence forefinger, title, index, from indicāre to disclose, show; see indicate

Derived forms of index

  • indexer, noun
  • indexless, adjective

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Cultural definitions for index

index

An alphabetical list of subjects treated in a book. It usually appears at the end of the book and identifies page numbers on which information about each subject appears.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.