The world's largest island (9)
I believe the answer is:
greenland
'the world's largest island' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for greenland that I've seen before include "Island mostly north of the Arctic circle" , "Large N Atlantic island" , "5 island north of 13" , "Large island self-governing province of Denmark" , "Danish self-governing island, the world's largest" .)