to describe something that is so sweet, that the words "ill" or "sick" just wont do. Illy is a word that comes from latin meaning "so fresh it's out of this world".
Daniel: Yo did you just see that Honda CRX
Mike: yeah that car was illy, ya dig homie slice.
Daniel: yeah that car was so illy!
Mike: yeah that car was illy, ya dig homie slice.
Daniel: yeah that car was so illy!
by Ace Dace March 06, 2011