[1] : The Collaborative International Dictionary of English v.0.48

madden \mad"den\, v. t. imp.  p. p. maddened; p. pr.  vb.
   n. maddening.
   1. to make mad; to drive to madness; to drive to insanity; to
      craze.
      1913 webster

   2. to make very angry; to enrage; to excite violently with
      passion.
      1913 webster
see also:
maddened maddening 

[2] : The Collaborative International Dictionary of English v.0.48

maddening \maddening\ adj.
   extremely annoying or displeasing.

   syn: annoying, exasperating, infuriating, vexing.
        wordnet 1.5

[3] : WordNet (r) 2.0

maddening
     adj : extremely annoying or displeasing; "his cavelier curtness of
           manner was exasperating"; "i've had an exasperating
           day"; "her infuriating indifference"; "the ceaseless
           tumult of the jukebox was maddening" syn: exasperating,
            infuriating, vexing
see also:
exasperating infuriating vexing 

[4] : Moby Thesaurus II by Grady Ward, 1.0

47 moby thesaurus words for "maddening":
   agitating, breathtaking, charged, cliff-hanging, disquieting,
   distracting, disturbing, electric, exciting, exhilarating,
   galvanic, heady, heart-expanding, heart-stirring, heart-swelling,
   heart-thrilling, impressive, inflammatory, intoxicating, jarring,
   jolting, mind-blowing, moving, overcoming, overmastering,
   overpowering, overwhelming, perturbing, piquant, provocative,
   provoking, ravishing, soul-stirring, spirit-stirring, stimulating,
   stimulative, stirring, striking, suspenseful, suspensive,
   tantalizing, telling, thrilling, thrilly, troubling, unsettling,
   upsetting

Maddening >> M Words
Maddening, definition of term: Maddening
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