Murphy has nothing to shoot at! (6)
I believe the answer is:
potato
'murphy' is the definition.
(synonyms)
'nothing to shoot at' is the wordplay.
'nothing' becomes 'O' (looks like zero - 0).
'to' means one lot of letters go next to another (I've seen this in other clues).
'shoot' becomes 'pot' (I've seen this in other clues).
'pot'+'at'='potat'
'o' put after 'potat' is 'POTATO'.
'has' is the link.
(Other definitions for potato that I've seen before include "The veg is too apt, oddly" , "The vegetable is just too pat" , "The humble spud" , "Spud (6)" , "Starchy tuber" .)