Business trick I rejected as dubious practice (9)
I believe the answer is:
collusion
'business trick' is the definition.
'collusion' can be an answer for 'trick' (thesaurus). I'm unsure of the 'business' bit.
'i rejected as dubious practice' is the wordplay.
I cannot really understand how this works, but
'i' is present in the answer.
'as' could be 'so' (I've seen this in other clues) and 'so' is present in the remaining letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for collusion that I've seen before include "Complicity between people for deceitful purpose" , "Secret or illegal conspiracy to deceive" , "Illegal co-operation for criminal purposes" , "Connivance" , "Secret deception" .)