Source : Free On-Line Dictionary of Computing

10base5
     
         An {Ethernet} network cabling specification
        operating at ten {Mbps}, "baseband" (as opposed to {radio
        frequency}), and with a maximum single cable length of 500
        metres.  This is normally carried on {RG8} cable.
     
        Compare {10base2}, {10baseT}.
     
        (2002-06-17)