Violent in future, perhaps (7)
I believe the answer is:
intense
'violent' is the definition.
('intense' can be similar in meaning to 'violent')
'in future perhaps' is the wordplay.
'future perhaps' becomes 'tense' (grammar).
'in'+'tense'='INTENSE'
(Other definitions for intense that I've seen before include "Extremely forceful" , "Of extreme force" , "amplified?" , "Strongly felt" , "Extremely emotional" .)