Can’t find any information on the yellow-eyed junco in your guide to rare birds? Check out your bird book's index. It’s an alphabetical list in the back of the book that catalogs all of the subjects covered by page number.

In financial terms, an index is a list of stocks that are traded on the stock market, such as the Dow Jones Indexes. “Index cards” were once used to catalog books in a library, but now they’re mostly used to prepare for a test or a presentation, thanks to computers. As a verb, index describes the action of creating an index, such as, “I’m going to index my photo collection on my computer, so I can find what I’m looking for.”

Definitions of index
  1. noun
    an alphabetical listing of names and topics along with page numbers where they are discussed
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    an index of all main words in a book along with their immediate contexts
    type of:
    list, listing
    a database containing an ordered array of items (names or topics)
  2. verb
    list in an index
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    make an index that refers from one point to the next
    type of:
    include in a list
  3. verb
    provide with an index
    index the book”
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    type of:
    furnish, provide, render, supply
    give something useful or necessary to
  4. verb
    adjust through indexation
    “The government indexes wages and prices”
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    type of:
    determine, influence, mold, regulate, shape
    shape or influence; give direction to
  5. noun
    a numerical scale used to compare variables with one another or with some reference number
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    margin of error, margin of safety, safety margin
    the margin required in order to insure safety
    type of:
    graduated table, ordered series, scale, scale of measurement
    an ordered reference standard
  6. noun
    a number or ratio (a value on a scale of measurement) derived from a series of observed facts; can reveal relative changes as a function of time
    synonyms: index number, indicant, indicator
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    BMI, body mass index
    a measure of someone's weight in relation to height; to calculate one's BMI, multiply one's weight in pounds and divide that by the square of one's height in inches; overweight is a BMI greater than 25; obese is a BMI greater than 30
    business index
    a statistical compilation that provides a context for economic or financial conditions
    leading indicator
    one of 11 indicators for different sections of the economy; used by the Department of Commerce to predict economic trends in the near future
    price index, price level
    an index that traces the relative changes in the price of an individual good (or a market basket of goods) over time
    short account
    the aggregate of short sales on an open market
    stock index, stock market index
    index based on a statistical compilation of the share prices of a number of representative stocks
    retail price index
    an index of changes in retail prices
    producer price index, wholesale price index
    an index of changes in wholesale prices
    CPI, consumer price index, cost-of-living index
    an index of the cost of all goods and services to a typical consumer
    type of:
    a statement or assertion of verified information about something that is the case or has happened
  7. noun
    a mathematical notation indicating the number of times a quantity is multiplied by itself
    synonyms: exponent, power
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    the highest power of a term or variable
    log, logarithm
    the exponent required to produce a given number
    degree of a term
    the sum of the exponents of the variables in the term
    degree of a polynomial
    the degree of the term in the polynomial that has the highest degree
    first degree
    a degree of one
    common logarithm
    a logarithm to the base 10
    Napierian logarithm, natural logarithm
    a logarithm to the base e
    type of:
    mathematical notation
    a notation used by mathematicians
  8. noun
    the finger next to the thumb
    synonyms: forefinger, index finger
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    type of:
    any of the terminal members of the hand (sometimes excepting the thumb)
Word Family

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