Twice stop Scot being savage (9)
I believe the answer is:
barbarian
'being savage' is the definition.
('barbarian' can be a synonym of 'savage')
'twice stop scot' is the wordplay.
'twice' indicates the doubling of some letters.
'stop' becomes 'bar' (bar can mean to stop or prevent).
'scot' becomes 'ian' (Scottish given name).
'bar' duplicated is 'barbar'.
'barbar'+'ian'='BARBARIAN'
(Other definitions for barbarian that I've seen before include "Crude" , "Uncivilised - Goth" , "uncivilised man" , "Brutish type" , "Uncultured, brutish" .)