The Collaborative International Dictionary of English v.0.48:

Mental \Men"tal\, a. [F., fr. L. mentalis, fr. mens, mentis, the
   mind; akin to E. mind. See Mind.]
   Of or pertaining to the mind; intellectual; as, mental
   faculties; mental operations, conditions, or exercise.
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         What a mental power
         This eye shoots forth!                   --Shak.
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   Mental alienation, insanity.

   Mental arithmetic, the art or practice of solving
      arithmetical problems by mental processes, unassisted by
      written figures.
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