Article supporting island state (4)
I believe the answer is:
iowa
'state' is the definition.
(Iowa is an example)
'article supporting island' is the wordplay.
'article' becomes 'a' (indefinite article).
'supporting' means one lot of letters go next to another (in a down clue, some letters go below others).
'island' becomes 'iow' (abbreviation for Isle of Wight**).
'a' put after 'iow' is 'IOWA'.
(Other definitions for iowa that I've seen before include "'Hawkeye State'" , "American state, capital Des Moines" , "US state, capital Des Moines" , "Midwest US state" , "US swing electoral state" .)