Saw fewer people in business (7,7)
I believe the answer is:
limited company
'saw' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'fewer people in business' is the wordplay.
'fewer people in' becomes 'limited' (I can't explain this - if you can you should believe this answer much more).
'business' becomes 'company' (company is a kind of business).
'limited'+'company'='LIMITED COMPANY'
(Other definitions for limited company that I've seen before include "desired by the semi-reclusive?" , "business" , "plc" .)