The phrase "other world" can have many synonyms, depending on the context and usage. It can refer to the supernatural, the afterlife, a parallel universe, or simply a different reality or perspective. Synonyms could include alternate dimension, parallel realm, spirit world, heaven or hell, dreamland, ethereal plane, or astral realm. In fiction and fantasy, the term "other world" might be replaced with terms like Narnia, Middle Earth, the Matrix, or Wonderland. Ultimately, the phrase "other world" is a flexible concept that can take on many different meanings and nuances.