Catch some violent rapscallions (6)
I believe the answer is:
entrap
'catch' is the definition.
(entrapping is a kind of catching)
'some violent rapscallions' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'ENTRAP' is hidden within 'violent rapscallions'.
(Other definitions for entrap that I've seen before include "Something to do with gin" , "Catch like parent" , "Parent (anag)" , "Deceive -- lead on" , "Lure into wrongdoing in order to arrest" .)