The DICT Development Group

  Tedium \Te"di*um\, n. [L. taedium, fr. taedet it disgusts, it
     wearies one.]
     Irksomeness; wearisomeness; tediousness. [Written also
     taedium.] --Cowper.
     [1913 Webster]
  
           To relieve the tedium, he kept plying them with all
           manner of bams.                          --Prof.
                                                    Wilson.
     [1913 Webster]
  
           The tedium of his office reminded him more strongly of
           the willing scholar, and his thoughts were rambling.
                                                    --Dickens.
     [1913 Webster]

  tedium
       n 1: the feeling of being bored by something tedious [syn: boredom,
             ennui]
       2: dullness owing to length or slowness [syn: tediousness, tiresomeness]

  77 Moby Thesaurus words for "tedium":
     alliteration, angst, anguish, anxiety, assonance, banality,
     boredom, changelessness, cheerlessness, chime, colorlessness,
     dingdong, discomfort, discomposure, discontent, dislike,
     displeasure, disquiet, dissatisfaction, doldrums, drabness, dread,
     dreariness, drone, dullness, emptiness, ennui, existential woe,
     flatness, grimness, harping, humdrum, inquietude, insipidity,
     insipidness, invariability, irksomeness, jingle, jingle-jangle,
     joylessness, lack of pleasure, long-windedness, malaise, monotone,
     monotony, nausea, near rhyme, nongratification, nonsatisfaction,
     painfulness, pitter-patter, repeated sounds, repetitiousness,
     repetitiveness, rhyme, routine, savorlessness, singsong,
     slant rhyme, spleen, stale repetition, staleness, tastelessness,
     tediousness, tiresomeness, trot, uncomfortableness, unease,
     uneasiness, unhappiness, unnecessary repetition, unpleasure,
     unsatisfaction, vapidity, vexation of spirit, wearisomeness,
     yawn
  
  

  TEDIUM, n.  Ennui, the state or condition of one that is bored.  Many
  fanciful derivations of the word have been affirmed, but so high an
  authority as Father Jape says that it comes from a very obvious
  source -- the first words of the ancient Latin hymn _Te Deum
  Laudamus_.  In this apparently natural derivation there is something
  that saddens.