# index

noun
in·​dex | \ ˈin-ˌdeks \
plural indexes or indices\ ˈin-​də-​ˌsēz \

## Definition of index

(Entry 1 of 2)

1 : a list (as of bibliographical information or citations to a body of literature) arranged usually in alphabetical order of some specified datum (such as author, subject, or keyword): such as
a : a list of items (such as topics or names) treated in a printed work that gives for each item the page number where it may be found
b : a list of publicly traded companies and their stock prices
c : a bibliographical analysis of groups of publications that is usually published periodically
d
2a : a number (such as a ratio) derived from a series of observations and used as an indicator or measure specifically
b : the ratio of one dimension of a thing (such as an anatomical structure) to another dimension
3a : a device (such as the pointer on a scale or the gnomon of a sundial) that serves to indicate a value or quantity
b : something (such as a physical feature or a mode of expression) that leads one to a particular fact or conclusion : indication
4 plural usually indices : a number or symbol or expression (such 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 {latex}\sqrt[3]{5}{/latex} to indicate the cube root of 5
5 : a character ☞ used to direct attention to a note or paragraph

called also fist

6 : 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

index

verb
indexed; indexing; indexes

Definition of index (Entry 2 of 2)

transitive verb

1a : to provide with an index
b : to list in an index all persons and places mentioned are carefully indexed
2 : to serve as an index of
3 : to regulate (wages, prices, interest rates, etc.) by indexation

intransitive verb

: to index something

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Verb

indexer noun

Synonyms: Noun

Synonyms: Verb

## Examples of index in a Sentence

Noun Look up the recipe for potato soup in the index. Potato soup is listed under “soup” in the index. The card catalog is an index to the materials in the library. the index on a scale Verb This search engine has indexed hundreds of millions of Web sites. indexed all the books in the library by category
Recent Examples on the Web: Noun The index is still on track to close out its third solid monthly gain in a row. The index is about economic freedom, not who rules whom. However, the stock index has been able to push itself back into positive territory for the year. The index had been down 34 points in the early going. The index was up 22.2 points on the quarter and up more than 50 points from the second quarter. The index at the heart of many 401(k) accounts is on track to close at an all-time high for the first time in more than two months, after soaring as much as 3.9% earlier in the morning. In 40 of the past 50 years, the stock market, as measured by the S&P 500 index, gained in value. Our Lynch screening model has shown impressive long-term performance, with an average annual gain since 1998 of 8.1%, versus 6.2% for the S&P 500 index in the same period. Recent Examples on the Web: Verb After 2022, the order will also index the $15 minimum wage for federal contractors to inflation, so it will be automatically adjusted to reflect changes in the cost of living going forward. Another option would be to simultaneously increase the gas tax further and index it to inflation. Several Republicans on Thursday announced their support for a plan by GOP Sens. Tom Cotton of Arkansas and Mitt Romney of Utah that would raise the minimum wage by a smaller amount more slowly and thereafter index it to inflation. Finally, the last Smart Scan task will re-index a Mac’s Spotlight database as well as rebuilding the mail search database. The bill would also index the minimum wage to inflation after reaching$15 an hour in 2025. On Tuesday, Republican Sens. Tom Cotton of Arkansas and Mitt Romney of Utah introduced a counterproposal to raise the minimum wage to \$10 by 2025 and then index the wage to inflation every two years. One option would be to index a minimum wage increase to the cost of living in each state instead of mandating an across-the-board rate. Search bots typically scan websites in order to rank and index them for search engine results.

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'index.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

## First Known Use of index

Noun

1561, in the meaning defined at sense 3a

Verb

1720, in the meaning defined at transitive sense 1a

## History and Etymology for index

Noun

Latin indic-, index, from indicare to indicate

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Time Traveler for index

## The first known use of index was in 1561

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## Statistics for index

Last Updated

4 May 2021

Cite this Entry

“Index.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/index. Accessed 9 May. 2021.

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More Definitions for index

index

noun

## English Language Learners Definition of index

(Entry 1 of 2)

: an alphabetical list at the end of a book that shows the page where each thing in the list can be found
: a group of related things that are in alphabetical or numerical order
: a sign or number that shows how something is changing or performing : a number that indicates changes in the level of something (such as a stock market) when it rises or falls

index

verb

English Language Learners Definition of index (Entry 2 of 2)

: 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

index

noun
in·​dex | \ ˈin-ˌdeks \
plural indexes or indices\ ˈin-​də-​ˌsēz \

## Kids Definition of index

(Entry 1 of 2)

1 : a list of names or topics (as in a book) given in alphabetical order and showing where each is to be found
2 : pointer sense 1 the index on a scale
3 : sign entry 1 sense 3, indication Prices are an index of business conditions.

index

verb
indexed; indexing

Kids Definition of index (Entry 2 of 2)

1 : to provide (as a book) with an index
2 : to list in an index The topics are indexed.

index

noun
in·​dex | \ ˈin-ˌdeks \
plural indexes or indices\ -​də-​ˌsēz \

## Medical Definition of index

1
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
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 juiceJournal of the American Medical Association
b : the ratio of one dimension of a thing (as an anatomical structure) to another dimension

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index

noun
in·​dex

## Legal Definition of index

(Entry 1 of 2)

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

Legal Definition of index (Entry 2 of 2)

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

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More from Merriam-Webster on index

Thesaurus: All synonyms and antonyms for index

Britannica English: Translation of index for Arabic Speakers

What made you want to look up index? Please tell us where you read or heard it (including the quote, if possible).

#### paean

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