The Collaborative International Dictionary of English v.0.48:

Discomfort \Dis*com"fort\, v. t. [imp. & p. p. Discomforted;
   p. pr. & vb. n. Discomforting.] [OF. desconforter, F.
   d['e]conforter, to discourage; pref. des- (L dis-) +
   conforter. See Comfort.]
   1. To discourage; to deject.
      [1913 Webster]

            His funeral shall not be in our camp,
            Lest it discomfort us.                --Shak.
      [1913 Webster]

   2. To destroy or disturb the comfort of; to deprive of quiet
      enjoyment; to make uneasy; to pain; as, a smoky chimney
      discomforts a family.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Discomfort \Dis*com"fort\, n. [OF. desconfort, F. d['e]confort.
   See Discomfort, v. t.]
   1. Discouragement. [Obs.] --Shak.
      [1913 Webster]

   2. Want of comfort; uneasiness, mental or physical;
      disturbance of peace; inquietude; pain; distress; sorrow.
      "An age of spiritual discomfort." --M. Arnold.
      [1913 Webster]

            Strive against all the discomforts of thy
            sufferings.                           --Bp. Hall.
      [1913 Webster]

WordNet (r) 3.0 (2006):

discomfort
    n 1: the state of being tense and feeling pain [syn:
         discomfort, uncomfortableness] [ant: comfort,
         comfortableness]
    2: an uncomfortable feeling of mental painfulness or distress
       [syn: discomfort, soreness, irritation]

Moby Thesaurus II by Grady Ward, 1.0:

97 Moby Thesaurus words for "discomfort":
   Schmerz, ache, aches and pains, afflict, agitate, angst, anguish,
   anxiety, bitterness, bleakness, boredom, bother, burden, care,
   cheerlessness, comfortlessness, depression, difficulty,
   discomposure, discontent, dislike, dismalness, dismay, displeasure,
   disquiet, dissatisfaction, distress, distressfulness, disturb,
   dolor, dread, dreariness, dullness, emptiness, ennui,
   existential woe, flatness, grief, grieve, grievousness, grimness,
   hardship, hurt, hurting, inconvenience, inquietude, irritation,
   joylessness, lack of pleasure, lament, lamentability, lamentation,
   load with care, malaise, misery, mourn, mournfulness, nausea,
   nongratification, nonsatisfaction, nuisance, pain, painfulness,
   pathos, perturb, pitiability, pitiableness, pitifulness, poignancy,
   put to it, regrettableness, sadness, savorlessness, sharpness,
   soreness, sorrow, sorrowfulness, spleen, staleness, suffering,
   tastelessness, tediousness, tedium, trouble, twinge,
   uncomfortableness, unease, uneasiness, unhappiness, unpleasure,
   unsatisfaction, upset, vexation, vexation of spirit, woebegoneness,
   woefulness, worry