Approaching the age of rebellion? (6)
I believe the answer is:
rising
I believe this clue is a double definition.
'approaching the age of' is the first definition.
(I've seen this before)
'rebellion?' is the second definition.
(I know that rebellion can be written as rising)
(Other definitions for rising that I've seen before include "In the ascendant" , "A revolt; getting up" , "working one's way up" , "Sloping up; rebellion" , "Hill" .)