Company, business (4)
I believe the answer is:
firm
I believe this clue is a double definition.
'company' is the first definition.
(firm can mean a company or business)
'business' is the second definition.
(I know that firm is a type of business)
(Other definitions for firm that I've seen before include "solid structure" , "Unflinching" , "Company; steady" , "commercial partnership" , "Unyielding business concern?" .)