Possibly not coy as a businessman (6)
I believe the answer is:
tycoon
'a businessman' is the definition.
(I know that tycoon is a type of businessman)
'possibly not coy' is the wordplay.
'possibly' indicates anagramming the letters.
'not'+'coy'='notcoy'
'notcoy' anagrammed gives 'TYCOON'.
'as' acts as a link.
(Other definitions for tycoon that I've seen before include "Rich and powerful businessman" , "Powerful industrialist" , "Big noise" , "Magnate, wealthy businessman" , "Plutocrat" .)