Fish turned around (3)
I believe the answer is:
dab
'fish' is the definition.
(dab is a type of fish)
'turned around' is the wordplay.
'turned' becomes 'bad' (I've seen this in another clue).
'around' is a reversal indicator.
'bad' back-to-front is 'DAB'.
(Other definitions for dab that I've seen before include "Apply small amounts (usually a liquid) to a surface" , "A fish; light touch" , "Digital radio" , "Expert; flat fish" , "Fingerprint - fish" .)