Flipping big city area taken over (4)
I believe the answer is:
anew
'over' is the definition.
(thesaurus)
'flipping big city area taken' is the wordplay.
'flipping' shows that the letters should be reversed in order.
'big city' becomes 'wa' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'area' becomes 'ne'.
'taken' means one lot of letters goes inside another.
'wa' in reverse letter order is 'aw'.
'aw' going around 'ne' is 'ANEW'.
Can you help me to learn more?
(Other definitions for anew that I've seen before include "Once more (poetic)" , "Wane in a different way, again" , "Afresh" , "From the beginning again" , "Again but differently" .)