Island firm threw out fur (5)
I believe the answer is:
corfu
'island' is the definition.
(Greek island)
'firm threw out fur' is the wordplay.
'firm' becomes 'co' (a firm is a company).
'threw out' indicates an anagram (I've seen 'thrown out' mean this).
'fur' anagrammed gives 'rfu'.
'co'+'rfu'='CORFU'
(Other definitions for corfu that I've seen before include "Greek island, a British protectorate in C 19" , "Largest Ionian Island" , "Largest of the Ionian Islands" , "Holiday location" , "part of Greece" .)