Island houses (3)
I believe the answer is:
cos
This clue could be a double definition.
'island' is the first definition.
(Greek island)
'houses' is the second definition.
Although both the answer and definition are plural nouns, I cannot understand how they can define each other.
Can you help me to learn more?
(Other definitions for cos that I've seen before include "Island in Mediterranean" , "healthy food" , "foreign island" , "providing unsatisfactory explanation?" , "Salad ingredient" .)