The term "millenniumism" refers to the belief in a coming era of great societal change or spiritual transformation. While there are no exact synonyms for this term, there are related concepts that carry similar meanings. For example, "eschatology" refers to the study of end times or the end of the world, and is often associated with religious prophecy. "Apocalypticism" refers to the belief in an imminent, catastrophic event that will bring about a new era of reality. "Utopianism" refers to the idea of a perfect or ideal society that can be achieved through human effort and cooperation. While these concepts may differ in their specific beliefs and connotations, they all share a sense of hope and anticipation for a better future.