Wikipedia
Maclisp
MACLISP (or Maclisp, sometimes styled MacLisp or MacLISP) is a dialect of the Lisp programming language. It originated at MIT's Project MAC (from which it derived its prefix) in the late 1960s and was based on Lisp 1.5. Richard Greenblatt was the main developer of the original codebase for the PDP-6; Jon L. White was responsible for its later maintenance and development. The name 'Maclisp' started being used in the early 1970s to distinguish it from other forks of PDP-6 Lisp, notably BBN Lisp.