peasouper

/ˈpiːˌsuːpər/
noun
  1. A very thick, dense fog, especially one that is yellow or gray due to pollution (historically common in London).
    • In old detective stories, a peasouper often sets the mood for a mysterious crime.
    • The city was blanketed by a peasouper so thick you could barely see your hand in front of your face.
    • The peasouper caused many accidents as drivers struggled to see the road.
Synonyms
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