Business rising with a takeover (4)
I believe the answer is:
coup
'takeover' is the definition.
(I've seen this in another clue)
'business rising' is the wordplay.
'business' becomes 'co' (short for company).
'rising' becomes 'up' (similar in meaning).
'co'+'up'='COUP'
'with a' is the link.
(Other definitions for coup that I've seen before include "A sudden exploit or rebellion" , "Sudden change, illegally or by force" , "triumph" , "Putsch" , "Successful exploit or action" .)