(in stories) a world that exists in addition to, and is like, the world that we know, but that is also different from it in important ways

The setting is a medieval English village called Wall, so named for the wall that separates the villagers from Stormhold, the parallel universe just beyond it. 故事发生在一个叫“墙村”的中世纪英国村庄里，之所以叫墙村，是因为有一堵高墙把村庄与墙另一边的平行宇宙“风暴禁域”分开。

a universe that may exist in addition to our own universe, but that is not known

He was a brilliant physicist who predicted the existence of parallel universes. 他是一位杰出的物理学家，预言了平行宇宙的存在。