Girl from the east put away in prison (7)
I believe the answer is:
newgate
'prison' is the definition.
(I've seen this before)
'girl from the east put away' is the wordplay.
'girl' becomes 'gwen' (**).
'from the east' says the letters should be written backwards.
'put away' becomes 'ate' (I've seen this in other clues).
'gwen' back-to-front is 'newg'.
'newg'+'ate'='NEWGATE'
'in' acts as a link.
(Other definitions for newgate that I've seen before include "Old London prison" , "London street" , "Former London prison" , "Stir in capital" , "Prison formerly standing on site of the Old Bailey" .)