Share in a business (5)
I believe the answer is:
stake
'share in a business' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for stake that I've seen before include "Wager; post" , "Wooden post; ante" , "A bet or sharpened stick" , "Money placed as bet" , "Deposit as a wager" .)