Boys seen around new estates (5)
I believe the answer is:
lands
'estates' is the definition.
('land' can be a synonym of 'estate')
'boys seen around new' is the wordplay.
'boys' becomes 'lads' (lad is a kind of boy).
'seen around' is an insertion indicator.
'new' becomes 'n'.
'lads' placed around 'n' is 'LANDS'.
(Other definitions for lands that I've seen before include "Obtains" , "See 21" , "Comes ashore" , "Alights" .)