Leading party thrashing youths around college to intimidate (5,3)
I believe the answer is:
Here is my best explanation:
'intimidate' is the definition.
(I've seen this before)
'leading party thrashing youths around college to' is the wordplay.
'leading party thrashing youths' becomes 'psych' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'around' indicates an anagram.
'college' becomes 'u' (abbreviation for University).
'uto' with letters rearranged gives 'out'.