Food shop to the left behind King's Cross (5)
I believe the answer is:
riled
'cross' is the definition.
(thesaurus)
'food shop to the left behind king's' is the wordplay.
'food shop' becomes 'deli' ('deli' can be a synonym of 'food shop').
'to the left' says the letters should be written in reverse (reading from right to left).
'behind' is a charade indicator (letters next to each other).
'king' becomes 'r' (r is abbreviation for rex).
'deli' back-to-front is 'iled'.
'iled' put after 'r' is 'RILED'.
(Other definitions for riled that I've seen before include "Made angry" , "Nettled" , "Cross" , "Annoyed" , "Irritated, provoked" .)