Board Thread:Lore Discussion/@comment-25196161-20140718180949/@comment-17114085-20150206110959

No, it means that they have a natural affinity with the Thu'um, like a dragon. And it means that they can absorb the souls of other dragons. It doesn't mean that he can be resurrected or anything like that.

PS.: The reason that Alduin was able to resurrect the dead dragons is because unlike mortals dragon souls aren't separated from the body when they die. The soul remains connected to the body and thus can be brought back by someone that knows how to. The only way to permanently kill a dragon is to separate the soul from the body, which can only be done by a Dragonborn that absorbs the soul.