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1

index

play
noun in·dex \ˈin-ˌdeks\

Definition of index

plural

indexes

or

indices

play \-də-ˌsēz\
  1. 1 a :  a device (as the pointer on a scale or the gnomon of a sundial) that serves to indicate a value or quantity b :  something (as a physical feature or a mode of expression) that leads one to a particular fact or conclusion :  indication

  2. 2 :  a list (as of bibliographical information or citations to a body of literature) arranged usually in alphabetical order of some specified datum (as author, subject, or keyword): as a :  a list of items (as topics or names) treated in a printed work that gives for each item the page number where it may be found b :  thumb index c :  a bibliographical analysis of groups of publications that is usually published periodically d :  a list of publicly traded companies and their stock prices

  3. 3 :  a list of restricted or prohibited material; specifically capitalized :  a formerly published list of books the reading of which was prohibited or restricted for Roman Catholics by the church authorities

  4. 4 plural usually indices :  a number or symbol or expression (as an exponent) associated with another to indicate a mathematical operation to be performed or to indicate use or position in an arrangement <3 is the index of the expression ∛5 to indicate the cube root of 5>

  5. 5 :  a character F used to direct attention to a note or paragraph —called also fist

  6. 6 a :  a number (as a ratio) derived from a series of observations and used as an indicator or measure; specifically :  index number b :  the ratio of one dimension of a thing (as an anatomical structure) to another dimension



Examples of index in a sentence

  1. Look up the recipe for potato soup in the index.

  2. Potato soup is listed under soup in the index.

  3. The card catalog is an index to the materials in the library.

  4. the index on a scale



Origin and Etymology of index

Latin indic-, index, from indicare to indicate


First Known Use: 1561


2

index

verb in·dex

Simple Definition of index

  • : to provide an index for (something, such as a book)

  • : to list or include (something) in an index

  • : to link wages, benefits, etc., to a measurement of changes in the price of goods and services so that they increase at the same rate

Source: Merriam-Webster's Learner's Dictionary

Full Definition of index

  1. transitive verb
  2. 1 a :  to provide with an index b :  to list in an index <all persons and places mentioned are carefully indexed>

  3. 2 :  to serve as an index of

  4. 3 :  to regulate (as wages, prices, or interest rates) by indexation

  5. intransitive verb
  6. :  to index something

indexer

noun

Examples of index in a sentence

  1. This search engine has indexed hundreds of millions of Web sites.

  2. <indexed all the books in the library by category>



1720

First Known Use of index

1720



INDEX Defined for Kids

1

index

play
noun in·dex \ˈin-ˌdeks\

Definition of index for Students

plural

indexes

or

indices

\ˈin-də-ˌsēz\
  1. 1 :  a list of names or topics (as in a book) given in alphabetical order and showing where each is to be found

  2. 2 :  pointer 1 <the index on a scale>

  3. 3 :  1sign 3, indication <Prices are an index of business conditions.>




2

index

play
verb in·dex

Definition of index for Students

indexed

indexing

  1. 1 :  to provide (as a book) with an index

  2. 2 :  to list in an index <The topics are indexed.>




Medical Dictionary

index

play
noun in·dex \ˈin-ˌdeks\

Medical Definition of index

plural

indexes

or

indices

\-də-ˌsēz\play
  1. 1:  index finger

  2. 2:  a list (as of bibliographical information or citations to a body of literature) arranged usually in alphabetical order of some specified datum (as author, subject, or keyword) <Index Medicus of the United States National Library of Medicine>

  3. 3a:  a ratio or other number derived from a series of observations and used as an indicator or measure (as of a condition, property, or phenomenon) <physiochemical indexes of the urine, the blood, and the gastric juice—Journal of the American Medical Association>b:  the ratio of one dimension of a thing (as an anatomical structure) to another dimension—see cephalic index, cranial index




Law Dictionary

1

index

noun in·dex

Legal Definition of index

  1. :  a numerical measure or indicator (as of inflation or economic performance) — see also consumer price index




2

index

transitive verb in·dex

Legal Definition of index

  1. :  to link (as wages, rates, or investments) to an index <under the contract wages were indexed to inflation>





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