Source : Free On-Line Dictionary of Computing

backplane
     
         A {printed circuit board} with slots
        into which other cards are plugged.
     
        A backplane,is typically just a connector and does not usually
        have many active components on it.  This contrasts with a
        {motherboard}.
     
        {Designing a backplane
        (http://www.iec.org/online/tutorials/design_backplane/index.html)}.
     
        (2002-09-08)