indices
n. countablen. the plural form of 'index'. It refers to lists of information or signs that show how something is changing.
n. the plural of 'index', referring to alphabetical lists of names or subjects with page references, or to statistical measures of change in economy or science.
The researcher checked the indices of several books.
Economists use various price indices to track how much the cost of living increases over time.
The library's digital indices allow scholars to cross-reference thousands of manuscripts that were previously catalogued only in separate, physical volumes.
From Latin indicēs.
The plural 'indices' is preferred in technical, mathematical, and financial contexts, whereas 'indexes' is more common for books.
the book's indicesthe book's indexesWhile 'indices' is technically correct, 'indexes' is the standard plural for back-of-book lists in general English.