Realm is pretty popular. From Latin regarding "royal jurisdiction. " Dimension is from the Latin "a measuring" so you could call them different measures of reality. Spheres could work.

"The correct answer is Cosmos. The word Universe refers to the entirety of all matter and energy, including all celestial bodies and forms of energy in space. Astronomy and cosmology are fields of study focused on understanding the nature, properties, and origins of the universe. The term cosmos is often used as a synonym for the universe and is derived from the Greek word kosmos, which means order or harmony. The ancient Greeks believed the universe was a perfectly ordered and harmonious system. Today, cosmos is often used in a more poetic or philosophical context than universe to refer to the larger philosophical questions inspired by our observations of the universe. The term cosmos emphasizes the idea of order and harmony in the universe and is often used to describe the beauty and mystery of the universe. Big Crunch: A theoretical scenario in which the expansion of the universe eventually reverses and all matter collapses back into a hot, dense singularity. Astronomy: ​The scientific study of celestial objects and phenomena in the universe, including stars, planets, galaxies, and black holes, as well as the properties, physics, and evolution of these objects. Supernova: ​A powerful and luminous explosion that occurs when a massive star reaches the end of its life and expels most of its mass in a massive burst of energy and radiation."