miasma  
noun [ C ]  literary uk/miˈæz.mə/ us/miˈæz.mə/
  (FOG)      
  臭气,瘴气
an unpleasant fog that smells bad
  A miasma of pollution hung in the air above Mexico City. 污染形成的瘴气弥漫在墨西哥城的上空。 
   (UNPLEASANT FEELING)      
 不良气氛
a very unpleasant general feeling or character of a situation or place
  After he lost his job, he sank into a miasma of poverty and despair. 失业后,他渐渐陷入贫困与绝望之中。