Rule about central part of locality set straight (7)
I believe the answer is:
realign
'set straight' is the definition.
(I've seen this before)
'rule about central part of locality' is the wordplay.
'rule' becomes 'reign' (reign is a kind of rule).
'about' indicates putting letters inside.
'central part of' indicates the central letters.
The central letters of 'locality' are 'al'.
'reign' enclosing 'al' is 'REALIGN'.
(Other definitions for realign that I've seen before include "to take a new line" , "Regroup" , "shift in position" , "Arrange again" , "Set straight" .)