Source : Free On-Line Dictionary of Computing

wormhole routing
     
         A property of a {message passing} system in which
        each part of a message is transmitted independently and one
        part can be forwarded to the next {node} before the whole
        message has been received.  All parts of a single message
        follow the same route.
     
        The independent parts are normally small, e.g. one 32-bit
        word.  This reduces the {latency} and the storage requirements
        on each node when compared with {message switching} where a
        node receives the whole message before it starts to forward it
        to the next node.  It is more complex than message switching
        because each node must keep track of the messages currently
        flowing through it.
     
        With {cut-through switching}, wormhole routing is applied to
        {packets} in a {packet switching} system so that forwarding of
        a packet starts as soon as its destination is known, before
        the whole packet had arrived.
     
        (2003-05-15)