Motorists circling about neighbourhood (4)
I believe the answer is:
area
'neighbourhood' is the definition.
(I've seen this before)
'motorists circling about' is the wordplay.
'motorists' becomes 'AA' (Automobile Association).
'circling' means one lot of letters goes inside another (circling can mean going around or containing).
'about' becomes 're' ('re' means regarding or about).
'aa' going around 're' is 'AREA'.
(Other definitions for area that I've seen before include "Surface measurement" , "'Tract, region (4)'" , "Region, zone" , "topic" , "Space occupied by something" .)