The term "dark obscuring matter" refers to the hypothetical matter that is believed to make up a significant portion of the universe's mass but cannot be detected by telescopes or any other instruments. There are several synonyms for this mysterious matter, including dark matter, invisible matter, non-luminous matter, and transparent matter. Other names include exotic matter, hidden matter, and shadow matter. The existence of dark obscuring matter is inferred from its gravitational effects on visible matter, such as galaxies and galaxy clusters. Despite decades of research and experimentation, scientists are still struggling to identify and directly detect this enigmatic substance.