unhoped unhoped-for unthought unthought-of
unhoped%5:00:00:unexpected:00 unhoped-for%5:00:00:unexpected:00 unthought%5:00:00:unexpected:00 unthought-of%5:00:00:unexpected:00
so unexpected as to have not been imagined
an unhoped-for piece of luck an unthought advantage an unthought-of place to find the key