Let everyone go to town centre (5)
I believe the answer is:
allow
'let' is the definition.
(I know that allow is a kind of let)
'everyone go to town centre' is the wordplay.
'everyone' becomes 'all' (all people).
'go to' means one lot of letters go next to another.
'town centre' becomes 'ow' (central letters of the word 'town').
'all'+'ow'='ALLOW'
(Other definitions for allow that I've seen before include "Licence" , "Permit, consent to" , "Permit or agree" , "Admit as acceptable" , "Permit or concede" .)