Overrule check on job centre (4)
I believe the answer is:
veto
'overrule' is the definition.
(I've seen this before)
'check on job centre' is the wordplay.
'check' becomes 'vet' (I've seen this before**).
'on' is a charade indicator (letters next to each other).
'centre' says to take the centre.
The middle of 'job' is 'o'.
'vet'+'o'='VETO'
(Other definitions for veto that I've seen before include "Overrule, forbid" , "Literally, 'I forbid'" , "black ball" , "Authoritative prohibition" , "Disallow" .)