Gosh – a funny trickster! (6)
I believe the answer is:
cooper
'funny trickster' is the definition.
The answer and definition can be both people as well as being singular nouns.
Perhaps you can see a link between them that I can't see?
'gosh a' is the wordplay.
'gosh' becomes 'coo'.
'a' becomes 'per' (eg 'one a day' means 'one per day').
'coo'+'per'='COOPER'
Can you help me to learn more?
(Other definitions for cooper that I've seen before include "Cask-maker" , "Barrel-maker" , "He makes and repairs barrels" , "Maker of barrels" , "Craftsman" .)