Bishop takes over grotty urban area (7)
I believe the answer is:
borough
'urban area' is the definition.
'borough' can be an answer for 'area' (a borough is an area of a city). I am not sure about the 'urban' bit.
'bishop takes over grotty' is the wordplay.
'bishop' becomes 'B' (abbreviation for bishop in chess).
'takes' means one lot of letters go next to another.
'over' becomes 'o' (cricket abbreviation).
'grotty' becomes 'rough' (I can't explain this - if you can you should believe this answer much more).
'b'+'o'+'rough'='BOROUGH'
Can you help me to learn more?
(Other definitions for borough that I've seen before include "London district" , "Local government division" , "Local district" , "Town with a corporation and special privileges" , "Important town" .)