Source : Free On-Line Dictionary of Computing

Lisp Machine
     
        1.  Any {machine} (whether notional or actual)
        whose instruction set is {Lisp}.
     
        2.  A line of {workstations} made
        by {Symbolics, Inc.} from the mid-1970s (having grown out of
        the {MIT AI Lab}) to late 1980s.  All system code for
        Symbolics Lisp Machines was written in {Lisp Machine Lisp}.
        Symbolics Lisp Machines were also notable for having had
        {space-cadet keyboards}.
     
        [More details and historical background?]
     
        {Lisp Machine Museum
       
     (http://kogs-www.informatik.uni-hamburg.de/~moeller/symbolics-info/symbolics.html)}.
     
        (2003-07-03)