Being under a cloud puts a damper on things (4)
I believe the answer is:
rain
'a damper on things' is the definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.
'being under a cloud' is the wordplay.
I cannot quite understand how this works, but
'a' is found in the answer.
The remaining letters 'rin' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'puts' acts as a link.
Can you help me to learn more?
(Other definitions for rain that I've seen before include "downfall?" , "eg A shower" , "Falling water" , "previous rule?" , "The ---, it ---eth every day (T.Night)" .)