1

index

noun in·dex \ ˈin-ˌdeks \
|Updated on: 12 Jun 2018
plural indexes or indices\ˈin-də-ˌsēz\
1 a : 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
2 : 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
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 : 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 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 : 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

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

Recent Examples of index from the Web

• These off-the-radar companies are just a few of the winners in the Russell 2000 index — which includes stocks of smaller companies with an average market value of $2.5 billion. • Now there is a new candidate: share buy-backs, which reached$189bn in the three months to March for firms in the S&P 500 index, a record high.
• Among the 20 cities included in the index, the largest increases were in Seattle (13 percent), Las Vegas (12.4 percent) and San Francisco (11.3 percent).
• The Russell 2000 index of smaller U.S. companies rose 1% Wednesday to 1616.37, topping its Jan. 23 closing high.
• The Russell 2000 index of smaller-company stocks lost 1 point, or 0.1 percent, to 1,562.
• The Russell 2000 index of smaller-company stocks gave up 30.15 points, or 1.9 percent, to 1,513.57.
• The Russell 2000 index of smaller-company stocks rose 19.20 points, or 1.3 percent, to 1,549.19.
• The Russell 2000 index of smaller-company stocks sank 56.18 points, or 3.6%.

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.

Origin and Etymology of index

Latin indic-, index, from indicare to indicate

index Synonyms

Related Words

dial, face, gauge (also gage);

2

index

verb
indexed; indexing; indexes
1 a : 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
: to index something

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

Recent Examples of index from the Web

• The Orange County district is no longer looking to use a rate benchmark indexed by the Metropolitan Water District.
• Kudlow also said that the next phase should include a lower capital gains rate -- and a rate that’s indexed for inflation.
• Retirees receive an average of 70 percent of their pre-retirement salary, and the amount is indexed to a constantly climbing minimum wage.
• This $10,000 limit applies for both single and married filers and is not indexed for inflation. • The gas tax was last raised in 1993 and it is not indexed to inflation. • By 1942, Reich Health Leader Leonardo Conti estimated that ten million Reich citizens had been indexed — 12% of the total population. • However, if the Standard & Poor's 500 index returns on average 8% a year, and if the life savings are locked down in a mutual fund that is indexed to the S&P 500, then shouldn't the annual withdrawal amount, to preserve those savings, be 8%? • The new number comes from the Oregon Department of Geology and Mineral Industries, which indexed 7,000 past landslides using laser-surveying technology. 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 1720 in the meaning defined at transitive sense 1a See Words from the same year NEW! Time Traveler index Synonyms Synonyms catalog (), enroll (also enrol), enter, inscribe, list, put down, record, register, schedule, slate; Near Antonyms Related Words book, card, file, note; Financial Definition of INDEX index What It Is An index is a statistical aggregate that measures change. In finance, they usually refer to measures of stock market performance or economic performance. How It Works Let's say we want to measure the stock price performance of the widget industry. There are currently four public companies that make widgets in the United States: Company A, Company B, Company C, and Company D. In the year 2000, when we started caring about the seedling U.S. widget industry, the four companies' stock prices were as follows: Company A$10
Company B     $8 Company C$12
Company D     $25 Total$55

To create an index, we simply set the total ($55) in the year 2000 equal to 100 and measure any future periods against that total. For example, let's assume that in 2001 the stock prices were: Company A$4
Company B     $38 Company C$12
Company D     $24 Total$78

Because \$78 is 41.82% higher than the 2000 base, the index is now at 141.82. Every day, month, year, or other period, the index can be recalculated based on current stock prices.

Note that this index is weighted by stock price (i.e., the larger the stock price, the more influence it has on the index). Indexes can be weighted by shares outstanding, market capitalization, or any other factors the indexer chooses. When new companies go public or existing companies founder, the indexer may add or delete companies from the index or "reweight" the index to accommodate stock splits or other factors.

Why It Matters

In finance, the most significant numbers in any given day's news are usually market indices. The Dow Jones Industrial Average is probably the best-known and most widely followed financial index in the world. It consists of 30 of the largest publicly traded firms in the United States. The S&P 500 Index is also very common, comprising over 70% of the total market cap of all stocks traded in the U.S. The Nasdaq Composite is a broad market index that encompasses about 4,000 issues traded on the Nasdaq National Market -- virtually every firm that trades on the exchange.

Indices are also used to gauge activity in an economy. Perhaps the best known economic index in the United States is the CPI, or Consumer Price Index, which measures inflation.

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

1

index

noun in·dex \ ˈin-ˌdeks \
plural indexes or indices \ˈin-də-ˌsēz\
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 1
• the index on a scale
3 : 1sign 3, indication
• Prices are an index of business conditions.

2

index

verb
indexed; indexing
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\
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
3 a : 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

1

index

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

2

index

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

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effigy

play

a figure representing a hated person

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