Coup put him off embracing head of regime (7)
I believe the answer is:
triumph
'coup' is the definition.
(thesaurus)
'put him off embracing head of regime' is the wordplay.
'off' indicates anagramming the letters.
'embracing' means one lot of letters goes inside another.
'head of' indicates taking the first letters.
The first letter of 'regime' is 'r'.
'put'+'him'='puthim'
'puthim' is an anagram of 'tiumph'.
'tiumph' placed around 'r' is 'TRIUMPH'.
(Other definitions for triumph that I've seen before include "Outstanding victory" , "Conquer, prevail" , "The exultation of victory" , "Be victorious" , "Crow" .)