Intimidation puts slip into swirling mist (9)
I believe the answer is:
terrorism
'intimidation' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Perhaps you can see a link between them that I don't see?
'slip into swirling mist' is the wordplay.
'slip' becomes 'error' (slip can mean an error or mistake).
'into' indicates putting letters inside.
'swirling' indicates an anagram.
'mist' with letters rearranged gives 'tism'.
'error' inserted inside 'tism' is 'TERRORISM'.
'puts' is the link.
Can you help me to learn more?
(Other definitions for terrorism that I've seen before include "Unauthorised violence for political ends" , "Action of revolutionaries" .)