Carry On Doctor , in one cut (8)
I believe the answer is:
continue
'carry on' is the definition.
('continue' can be a synonym of 'carry on')
'doctor in one cut' is the wordplay.
'doctor' indicates an anagram.
'in'+'one'+'cut'='inonecut'
'inonecut' anagrammed gives 'CONTINUE'.
(Other definitions for continue that I've seen before include "Carry on" , "Persist" , "Proceed" , "Go on without stopping" , "Don't stop, keep going" .)