Source : Free On-Line Dictionary of Computing

token ring
     
        A computer {local area network} arbitration scheme in which
        conflicts in the transmission of messages are avoided by the
        granting of "tokens" which give permission to send.  A station
        keeps the token while transmitting a message, if it has a
        message to transmit, and then passes it on to the next
        station.
     
        Often, "Token Ring" is used to refer to the {IEEE 802.5} token
        ring {standard}, which is the most common type of token ring.
     
        {Usenet} newsgroup: {news:comp.dcom.lans.token-ring}.