Former postman, one making a new life abroad (5)
I believe the answer is:
expat
'one making a new life abroad' is the definition.
(expatriate)
'former postman' is the wordplay.
'former' becomes 'ex' (prefix meaning former or onetime).
'postman' becomes 'pat' (children's TV character Postman Pat).
'ex'+'pat'='EXPAT'
(Other definitions for expat that I've seen before include "Person living permanent in a foreign country" , "overseas settler" , "Emigre" , "Degrade" , "Former countryman" .)