The Jargon File (version 4.4.7, 29 Dec 2003):

livelock
 /li:v'lok/, n.

    A situation in which some critical stage of a task is unable to finish
    because its clients perpetually create more work for it to do after they
    have been serviced but before it can clear its queue. Differs from 
    deadlock in that the process is not blocked or waiting for anything, but
    has a virtually infinite amount of work to do and can never catch up.


The Free On-line Dictionary of Computing (30 December 2018):

livelock

    /li:v'lok/ When two or more processes continuously
   change their state in response to changes in the other
   process(es) without doing any useful work.

   This is similar to deadlock in that no progress is made but
   differs in that neither process is blocked or waiting for
   anything.

   A human example of livelock would be two people who meet
   face-to-face in a corridor and each moves aside to let the
   other pass, but they end up swaying from side to side without
   making any progress because they always move the same way at
   the same time.

   [Jargon File]

   (1998-07-05)