The Maclisp dialect used on the LISP Machine. The many extensions to Maclisp include vectoRS, closures, flavoRS, stack groups, locatives, and {invisible pointeRS}. Currently supported by {Lisp Machines, Inc.} and Symbolics. ["LISP Machine Manual", D. Weinreb and D. Moon, MIT AI Lab, 1981]. (1997-03-18)