Business folk are primarily chaps (6)
I believe the answer is:
agents
'business folk' is the definition.
(an agent may organise transactions for a company)
'are primarily chaps' is the wordplay.
'primarily' says to take the initial letters.
'chaps' becomes 'gents' ('gent' can be a synonym of 'chap').
The first letter of 'are' is 'a'.
'a'+'gents'='AGENTS'
(Other definitions for agents that I've seen before include "They act for others" , "Sales reps" , "Representatives" , "They act for actors" , "They operate on behalf of others" .)