The gaffer in the van? (7)
I believe the answer is:
foreman
'the gaffer' is the definition.
('foreman' can be a synonym of 'gaffer')
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for foreman that I've seen before include "Gaffer, boss" , "Fellow in charge" , "spokesman" , "Supervising worker" , "Male supervisor" .)