Casual visit around centre of Liverpool (5)
I believe the answer is:
stray
'casual' is the definition.
(thesaurus)
'visit around centre of liverpool' is the wordplay.
'visit' becomes 'stay' (I've seen this before).
'around' means one lot of letters goes inside another.
'centre of' indicates the central letters.
The middle letter of 'liverpool' is 'r'.
'stay' going around 'r' is 'STRAY'.
(Other definitions for stray that I've seen before include "Wander; be unfaithful" , "Deviate" , "out of place" , "Appearing occasionally" , "Wander from the path" .)