Animal back in flat urban surroundings (6)
I believe the answer is:
brutal
'animal' is the definition.
(thesaurus)
'back in flat urban surroundings' is the wordplay.
'back' shows that the letters should be reversed in order.
'in' says the answer is hidden in the clue.
'laturb' is hidden in the letters of 'flat urban surroundings'.
'laturb' backwards is 'BRUTAL'.
(Other definitions for brutal that I've seen before include "Rottweiler" , "Cruel, heartless" , "Vicious" , "Savage and cruel" , "Very cruel and beastly" .)