On the street I run activity (4)
I believe the answer is:
Here is my best explanation:
'activity' is the definition.
'on the street i run' is the subsidiary indication.
'on' is a charade indicator (letters next to each other).
'the street' becomes 'st'.
'run' becomes 'r' (cricket abbreviation).
'st'+'i' is 'sti'.
(Other definitions for stir that I've seen before include "Arouse; commotion", "Slight movement", "Prison (sl.); agitate", "Prison; agitation", "Move around - prison", "Wake; commotion", "Mix or agitate", "Excite emotionally", "Move around in a liquid" and "Get moving".)