A sign of cold perhaps (6)
I believe the answer is:
sneeze
'a sign of cold' is the definition.
The definition and answer can be both states of affairs as well as being singular nouns.
Maybe there's a link between them I don't understand?
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for sneeze that I've seen before include "Sudden, involuntary and noisy spasm" , "Violent, involuntary expulsion of breath" , "See Zen at the sign of a cold" , "Sternutation- see Zen (anag)" , "coming from cold" .)