Wandering deserter entering Morecambe? (7)
I believe the answer is:
erratic
'wandering' is the definition.
(synonyms)
'deserter entering morecambe?' is the wordplay.
'deserter' becomes 'rat' (I've seen this before).
'entering' is an insertion indicator.
'morecambe?' becomes 'eric' (I've seen this in other clues).
'rat' inserted inside 'eric' is 'ERRATIC'.
(Other definitions for erratic that I've seen before include "Cartier (anag.)" , "on irregular path" , "Volatile" , "Fickle" , "Irregular and unpredictable" .)