Index

Part of speech: noun, verb

Pronunciation: /ˈɪndɛks/

Definitions

1. A systematic list of items, topics, or names arranged in alphabetical or numerical order for easy reference
2. A record that systematically arranges subjects, names, or entries in a logical order for effortless access
3. A structured compilation of entries, topics, or names organized sequentially for quick reference or retrieval

Etymology: Latin "index" originally meant "a discoverer, informer, spy" as well as "an indicator, the forefinger, a title or superscription." The forefinger sense is the telling one: the finger that points things out gave its name to the tool that points readers to things. The Latin noun comes from "indicō," meaning "point out" or "show," which is also the source of the English verb "indicate." The word reached English directly from Latin, so its connection to pointing is still visible in the family of "index," "indicate," and "indication." A book's index is, in effect, a set of pointing fingers that direct the reader to a page. The Latin sense of "informer" is a reminder that the root idea is revealing or exposing something, which is what the index does when it brings a hidden item to the surface.

Synonyms: directory, list, catalog, register, guide