Can cause trouble (4)
I believe the answer is:
stir
This clue is a double definition.
'can' is the first definition.
(thesaurus)
'cause trouble' is the second definition.
(I've seen this before)
(Other definitions for stir that I've seen before include "can > go forth" , "A slangy prison - whisk it" , "jail" , "fuss" , "Commotion to mix" .)