She's back from July rebellion (5)
I believe the answer is:
beryl
'she's' is the definition.
'back from july rebellion' is the wordplay.
'back' says the letters should be written in reverse.
'from' says the answer is hidden in the clue.
'lyreb' is hidden within 'july rebellion'.
'lyreb' reversed gives 'BERYL'.
(Other definitions for beryl that I've seen before include "Girl's name; gem" , "Blue, green or yellow mineral, sometimes a gemstone" , "Pale greenish" , "Precious stone of which emerald is a variety" , "Gemstone (for Ms Bainbridge?)" .)