1. Of or related to or containing sulphur or derived from sulphur
   "The sulphurous smell of rotten eggs filled the air";
   - sulfurous [N. Amer], sulfureous [US], sulphureous [Brit, Cdn]
    
2. Harsh or corrosive in tone
   "a sulphurous denunciation";
   - acerb, acerbic, acid, acrid, bitter, blistering, caustic, sulfurous [N. Amer], virulent, vitriolic, acidulous
    
3. Characterized by oppressive heat and humidity
   "the sulphurous atmosphere preceding a thunderstorm"; "the summer was sulphurous and oppressive";
   - sultry, stifling, sulfurous [N. Amer]

See also: hot, unpleasant

Encyclopedia: Sulphurous