The Collaborative International Dictionary of English v.0.48:

cross-index \cross-index\ n.
   a reference at one place in a work to information at another
   place in the same work.

   Syn: cross-reference.
        [WordNet 1.5]

The Collaborative International Dictionary of English v.0.48:

cross-index \cross-index\ v. t.
   to provide cross-references in (a book or other document).

   Syn: cross-reference.
        [PJC]

WordNet (r) 3.0 (2006):

cross-index
    n 1: a reference at one place in a work to information at
         another place in the same work [syn: cross-reference,
         cross-index]
    v 1: make an index that refers from one point to the next;
         "These references are cross-indexed"