Reject bad route going round centre of Hull (4,3)
I believe the answer is:
rule out
'reject' is the definition.
(thesaurus)
'bad route going round centre of hull' is the wordplay.
'bad' indicates an anagram.
'going round' indicates putting letters inside.
'centre of' indicates the central letters.
The middle of 'hull' is 'ul'.
'route' anagrammed gives 'reout'.
'reout' placed around 'ul' is 'RULE OUT'.
(Other definitions for rule out that I've seen before include "Decide against" , "Dismiss from consideration" , "discount" , "Eliminate from consideration - using drawing stick?" , "Exclude as irrelevant or inadmissible" .)