Holding racket inside (3)
I believe the answer is:
din
'holding racket inside' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'holding racket inside' is the wordplay.
'inside' indicates the answer is hidden within the clue.
'DIN' is hidden within 'holding racket'.
Can you help me to learn more?
(Other definitions for din that I've seen before include "'Loud, harsh noise (3)'" , "'Continuous, unpleasant noise (3)'" , "Loud and long noise" , "Loud harsh hoise" , "Unwanted noise" .)