资料来源 : Free On-Line Dictionary of Computing

normal order reduction
     
        Under this {evaluation strategy} an expression is evaluated by
        reducing the leftmost outermost {redex} first.  This method
        will terminate for any expression for which termination is
        possible, whereas {applicative order reduction} may not.  This
        method is equivalent to passing arguments unevaluated because
        arguments are initially to the right of functions applied to
        them.  See also {computational adequacy theorem}.