What does indices mean?
“Indices” is the plural form of “index,” a word used for organized lists or systems that help people locate information, track records, or compare values. In books, indices may point to names, topics, or passages. In computing, search indices allow records to be found efficiently, while in statistics and the sciences, indices provide values against which changes or relationships can be measured. The plural “indices” is especially common in formal, academic, mathematical, and technical writing, although “indexes” is also accepted and is often heard in modern computing contexts. Both forms ultimately derive from Latin, with “indices” preserving the Latin plural directly. The word is useful because it names a fundamental principle of organization: a carefully structured set of pointers that makes a larger body of information easier to navigate.
plural nounPlural of index: ordered lists or systems used to locate information, organize records, or show values against a reference. The term can also refer to a set of numerical or categorical indicators.
- Ordered lists, often arranged alphabetically, that identify and help locate information.
- Systems of labels or numerical values used to organize and retrieve records, especially in computing and data analysis.
- Sets of figures or symbols used to express relationships, especially in mathematics and the sciences.
"The indices at the back of the atlas make it easy to locate each country and its major cities."
"The library has updated its author and subject indices."
"The researchers compared several economic indices over the previous decade."
The standard plural of “index”; “indexes” is also widely accepted, especially in computing and general modern usage.
"The search engine updates its indices continuously."
English borrowed the Latin plural “indices” and kept it alongside the modern plural “indexes,” giving the word two respectable paths into the same page.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does indices come from?
The singular “index” comes from Latin index, meaning “pointer” or “indicator,” a word associated with the extended forefinger used to point. Latin formed the plural “indices,” which English borrowed directly and continues to use, especially in formal and technical contexts. English later developed “indexes” as another plural form, particularly common in general and computational usage.
How indices is actually used
“Indices” is the traditional plural of “index” and is especially common in formal, mathematical, scientific, and bibliographic contexts. “Indexes” is also standard and may be preferred in general usage, particularly when referring to computer databases or search systems.
Easily confused with indices
Both “indices” and “indexes” are accepted plural forms of “index,” but “indices” is especially common in formal, mathematical, and academic contexts, while “indexes” is often used in computing and general modern usage.
An index locates and lists entries, whereas an appendix contains supplementary material appended to the main text.