Business transaction in wood (4)
I believe the answer is:
deal
I believe this clue is a double definition.
'business transaction' is the first definition.
(I've seen this before)
'wood' is the second definition.
(I know that deal is a type of wood)
'in' acts as a link.
(Other definitions for deal that I've seen before include "Kent resort" , "Sawn wood" , "What business folk do" , "Transact" , "Business transaction of timber." .)