Becoming active again (9)
I believe the answer is:
renascent
'becoming active again' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for renascent that I've seen before include "Making a comeback" , "Becoming active again" , "Entrances (anag.); having new vitality" , "becoming effective again" , "coming back to life again" .)