The Collaborative International Dictionary of English v.0.48:

Uncomfortable \Un*com"fort*a*ble\, a.
   1. Feeling discomfort; uneasy; as, to be uncomfortable on
      account of one's position.
      [1913 Webster]

   2. Causing discomfort; disagreeable; unpleasant; as, an
      uncomfortable seat or situation.
      [1913 Webster]

            The most dead, uncomfortable time of the year.
                                                  --Addison.
      [1913 Webster] -- Un*com"fort*a*ble*ness, n. --
      Un*com"fort*a*bly, adv.
      [1913 Webster]

WordNet (r) 3.0 (2006):

uncomfortably
    adv 1: in physical discomfort; "she lay on the couch, her body
           uncomfortably twisted" [ant: comfortably]