Herod's other island? (6)
I believe the answer is:
rhodes
'island?' is the definition.
(Greek island)
'herod's other' is the wordplay.
'other' is an anagram indicator.
'herods' anagrammed gives 'RHODES'.
(Other definitions for rhodes that I've seen before include "Horsed around on the Greek island" , "Colonial businessman" , "Greek island - British-born South African statesman" , "See 21 Down" , "Largest island of the Dodecanese" .)