Lisp Machine 1. (architecture) Any machine (whether notional or actual) whose instruction set is Lisp.
2. (hardware, operating system) 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. Last updated: 2003-07-03