lisp 1.5

from The Free On-line Dictionary of Computing (8 July 2008)

LISP 1.5

   The second version of {Lisp}, successor to {LISP 1}.
   Developed at {MIT} in 1959.  Followed by LISP 1.75, LISP 1.9,
   {Lisp 2} and many other versions.