Truncheon used in the dark cabaret (9)
I believe the answer is:
nightclub
'cabaret' is the definition.
(I know that cabaret can be written as nightclub)
'truncheon used in the dark' is the wordplay.
I cannot quite see how this works, but
'truncheon' could be 'club' (I've seen this in another clue) and 'club' is present in the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found within the answer.
The remaining letters 'nigh' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for nightclub that I've seen before include "Where one might have room to swing" , "cabaret" , "Venue for late shows" , "Entertainment centre" , "one of the high spots" .)