Source : Webster's Revised Unabridged Dictionary (1913)

Interconnection \In`ter*con*nec"tion\, n.
   Connection between; mutual connection.

Source : WordNet®

interconnection
     n 1: a state of being connected reciprocally; "an interconnection
          between the two buildings" [syn: {interconnectedness}]
     2: (computer science) the act of interconnecting (wires or
        computers or theories etc.)