Merchants drove aimlessly around north and south (7)
I believe the answer is:
vendors
'merchants' is the definition.
(vendor is a kind of merchant)
'drove aimlessly around north and south' is the wordplay.
'aimlessly' is an anagram indicator (the letters rearranged chaotically or aimlessly).
'around' is an insertion indicator.
'north' becomes 'N' (abbreviation).
'and' says to put letters next to each other.
'south' becomes 's' (abbreviation).
'drove' with letters rearranged gives 'vedor'.
'vedor' enclosing 'n' is 'vendor'.
'vendor'+'s'='VENDORS'
(Other definitions for vendors that I've seen before include "Salesmen" , "They sell things" , "They sell in Latin" , "Rev nods to Latin sellers" , "Property sellers" .)