A bad atmosphere (3)
I believe the answer is:
fug
This might be a double definition.
'a bad' is the first definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'atmosphere' is the second definition.
(fug is a kind of atmosphere)
Can you help me to learn more?
(Other definitions for fug that I've seen before include "Fetidity" , "Close atmosphere" , "Warm, stuffy atmosphere" .)