adjective (a)

• conducive to or feeling mental discomfort(adj.all)

  Example:
  This kind of life can prove disruptive and uncomfortable.
  The uncomfortable truth.
  Grew uncomfortable beneath his appraising eye.
  An uncomfortable way of surprising me just when I felt surest.
  The teacher's presence at the conference made the child very uncomfortable.
  

  Antonym:
  comfortable
  

  source: wordnet30
• providing or experiencing physical discomfort(adj.all)

  Example:
  An uncomfortable chair.
  An uncomfortable day in the hot sun.
  

  Antonym:
  comfortable, comfy
  

  source: wordnet30
• Feeling discomfort; uneasy; as, to be uncomfortable on account of one's position.(adjective)

  source: webster1913