Source : Webster's Revised Unabridged Dictionary (1913)

Noisome \Noi"some\, a. [For noysome, fr. noy for annoy. See
   {Annoy}.]
   1. Noxious to health; hurtful; mischievous; unwholesome;
      insalubrious; destructive; as, noisome effluvia. ``Noisome
      pestilence.'' --Ps. xci. 3.

   2. Offensive to the smell or other senses; disgusting; fetid.
      ``Foul breath is noisome.'' --Shak. -- {Noi"some*ly}, adv.
      -- {Noi"some*ness}, n.

   Syn: Noxious; unwholesome; insalubrious; mischievous;
        destructive.

   Usage: {Noisome}, {Noxious}. These words have to a great
          extent been interchanged; but there is a tendency to
          make a distinction between them, applying noxious to
          things that inflict evil directly; as, a noxious
          plant, noxious practices, etc., and noisome to things
          that operate with a remoter influence; as, noisome
          vapors, a noisome pestilence, etc. Noisome has the
          additional sense of disqusting. A garden may be free
          from noxious weeds or animals; but, if recently
          covered with manure, it may be filled with a noisome
          smell.

Source : WordNet®

noisome
     adj 1: causing or able to cause nausea; "a nauseating smell";
            "nauseous offal"; "a sickening stench" [syn: {nauseating},
             {nauseous}, {loathsome}, {offensive}, {sickening}, {vile}]
     2: offensively malodorous; "a putrid smell" [syn: {fetid}, {foetid},
         {foul}, {foul-smelling}, {funky}, {smelly}, {putrid}, {stinking}]