noun

index

IHN-dehks

noun

An alphabetical list at the back of a book showing where topics can be found.

"I checked the index to find the page on tax deductions."

A number used to track or measure changes in something, such as prices or performance.

"The stock market index fell three percent today."

A sign or measure that indicates something.

"Unemployment is often used as an index of economic health."

verb

To create an index for, or to list systematically.

"The librarian spent weeks indexing the archive."

To adjust a value in line with another measure, especially to account for inflation.

"Pensions are indexed to inflation each year."

How to Use Index

Learner’s notes

In plain EnglishA list, number, or sign used to locate or measure something.

Common pairings

stock market index index of prices indexed to inflation index finger

indexed past tense, indexes plural, indices plural, index's plural, indexes singular

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I checked the _____ to find the page on tax deductions.

From Latin index, "forefinger, indicator, sign," from indicare, "to point out" — the same root as indicate.