Admit everybody to the town centre (5)
I believe the answer is:
allow
'admit' is the definition.
(allowing is a kind of admiting)
'everybody to the town centre' is the wordplay.
'everybody' becomes 'all' (I've seen this before).
'to the town centre' becomes 'ow' (central letters of the word 'town').
'all'+'ow'='ALLOW'
(Other definitions for allow that I've seen before include "OK" , "Sanction" , "Permit, let happen" , "Permit or concede" , "Give leave to" .)