Traditional gear was in the van — the person driving starts off jerkily (10)
I believe the answer is:
lederhosen
'person driving starts off jerkily' is the definition.
I can't judge whether this defines the answer.
'traditional gear was in the van' is the wordplay.
I cannot really understand how this works, but
'was in the van' could be 'led' (to go 'in the van' is to go at the front) and 'led' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
'the' acts as a link.
Can you help me to learn more?
(Other definitions for lederhosen that I've seen before include "Bavarian leather shorts" , "Alpine shorts" , "trousers displayed" , "Short leather trousers with braces" , "German outfit" .)