a note or group of notes referring the reader to material elsewhere.
cross-in•dexPronunciation: (krôs'in'deks, kros'-), [key]
to provide with cross references or with a cross-referenced index.
to refer by a note or indication of location to related material, as in an index, book, or article; contain cross references: Footnotes cross-index to the appendix and bibliography.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.