That show you're referring to is still going, currently going through some filler episodes but it should be back to canon in the new year. The next generation has just started as well.
As /u/ZenoArrow pointed out, it means "dawn" or in some contexts, "in the event... (of)"
It's used as the title for Akatsuki no Yona (Yona of the Dawn) but is otherwise only really known for being a certain group of characters from a certain anime which was implicated.
There are also a few characters who share the name, such as Akatsuki Ousawa. But that would refer to an individual and not a group.