Alienated participants in protest rang editor (9)
I believe the answer is:
estranged
'alienated' is the definition.
(synonyms)
'participants in protest rang editor' is the wordplay.
'participants in' indicates the answer is hidden within the clue.
'ESTRANGED' is hidden in the letters of 'protest rang editor'.
(Other definitions for estranged that I've seen before include "Sad regent (anag) - disaffected" , "Split" , "Cut off" , "Alienated, disaffected" , "A nerd gets (anag) - separated" .)