Stir made by platoon leader originally wearing symbol of rank (6)
I believe the answer is:
splash
'stir' is the definition.
(both can mean a commotion)
'platoon leader originally wearing symbol of rank' is the wordplay.
'originally' indicates taking the first letters.
'wearing' is an insertion indicator.
'symbol of rank' becomes 'sash' (part of a military uniform).
The first letters of 'platoon leader' is 'pl'.
'pl' put inside 'sash' is 'SPLASH'.
'made by' acts as a link.
(Other definitions for splash that I've seen before include "Dash with liquid" , "Excitement" , "Lead newspaper story" , "Spatter liquid about" , "Effect of body hitting water" .)