Traveller settling finally in Antrim, possibly (7)
I believe the answer is:
migrant
'traveller' is the definition.
(I know that migrant is a type of traveller)
'settling finally in antrim possibly' is the wordplay.
'finally' says to take the final letters.
'in' indicates putting letters inside.
'possibly' indicates anagramming the letters.
The last letter of 'settling' is 'g'.
'antrim' anagrammed gives 'mirant'.
'g' inserted into 'mirant' is 'MIGRANT'.
(Other definitions for migrant that I've seen before include "Moving across territories" , "relocating" , "Itinerant" , "Ring mat (anag.)" , "One travelling to find work" .)