monotonical

from The Collaborative International Dictionary of English v.0.48

Monotonic \Mon`o*ton"ic\, Monotonical \Mon`o*ton"ic*al\, a.
   1. Of, pertaining to, or uttered in, a monotone; monotonous.
      "Monotonical declamation." --Chesterfield.
      [1913 Webster]

   2. (Math.) Always increasing or always decreasing, as the
      value of the independent variable increases; -- of a
      function.
      [PJC]