Wake up girl in uniform? Quite the opposite! (5)
I believe the answer is:
rouse
'wake up' is the definition.
(I've seen this before)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for rouse that I've seen before include "Inspire" , "Prod" , "Bumper" , "Cause to become awake" , "Stir up; excite" .)