Dissident in this place has mark of approval curtailed (7)
I believe the answer is:
heretic
'dissident' is the definition.
(thesaurus)
'this place has mark of approval curtailed' is the wordplay.
'this place' becomes 'here' (I've seen this in other clues).
'has' means one lot of letters go next to another.
'mark of approval' becomes 'tick' (I've seen this before).
'curtailed' means to remove the last letter.
'tick' with its last letter taken away is 'tic'.
'here'+'tic'='HERETIC'
'in' acts as a link.
(Other definitions for heretic that I've seen before include "his controversial views" , "Non-believer" , "One with unorthodox opinions" , "dissenter" , "One breaking with orthodox beliefs" .)