interstellar

An interstellar object or event is one that involves two or more stars. The word can also describe something related to space outside of our solar system.

When we talk about the universe being vast and full of mysteries, scientists might use the term "interstellar" to describe certain phenomena they've discovered. For instance, if a new planet has been found orbiting another star in a far-off galaxy, astronomers might say it's an interstellar body. The word is also used when discussing things that travel between stars, like comets or space debris.