Ardent Green wants change of leader (7)
I believe the answer is:
zealous
'ardent' is the definition.
(synonyms)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for zealous that I've seen before include "Very devoted to a cause" , "Extremely enthusiastic" , "'Enthusiastic, keen (7)'" , "Ardently active" , "Highly enthusiastic" .)