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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Monotonous \Mo*not"o*nous\, a. [Gr. ?; mo`nos alone, single + ?
      tone. See Tone.]
      Uttered in one unvarying tone; continued with dull
      uniformity; characterized by monotony; without change or
      variety; wearisome. -- Mo*not"o*nous*ly, adv. --
      Mo*not"o*nous*ness, n.
      [1913 Webster]