Source : Free On-Line Dictionary of Computing

full laziness
     
         A transformation, described by
        Wadsworth in 1971, which ensures that subexpressions in a
        function body which do not depend on the function's arguments
        are only evaluated once.  E.g. each time the function
     
        	f x = x + sqrt 4
     
        is applied, (sqrt 4) will be evaluated.  Since (sqrt 4) does
        not depend on x, we could transform this to:
     
        	f x = x + sqrt4
        	sqrt4 = sqrt 4
     
        We have replaced the dynamically created (sqrt 4) with a
        single shared constant which, in a {graph reduction} system,
        will be evaluated the first time it is needed and then updated
        with its value.
     
        See also {fully lazy lambda lifting}, {let floating}.
     
        (1994-11-09)