(in a book or set of books) an alphabetical list of names, subjects, etc. with reference to the pages on which they are mentioned.
"clear cross references supplemented by a thorough index"
a sign or measure of something.
"exam results may serve as an index of the teacher's effectiveness"
record (names, subjects, etc.) in an index.
"the list indexes theses under regional headings"
link the value of (prices, wages, or other payments) automatically to the value of a price index.
"the Supreme Soviet passed legislation indexing wages to prices"