Immigrants' island (5)
I believe the answer is:
ellis
'immigrants' island' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for ellis that I've seen before include "American island" , "who wrote sexy books?" , "Havelock --, English essayist" , "- - Peters (Cadfael writer)" , "- Peters, wrote Brother Cadfael books" .)