Learner's definition of UNIVERSE
all of space and everything in it including stars, planets, galaxies, etc.
an area of space or a world that is similar to but separate from the one that we live in
the people, places, experiences, etc., that are associated with a particular person, place, or thing
The college campus is its own little universe. [=world]
Her young son is the center of her universe. [=the most important part of her life]
New York City is the center of the publishing universe.