No one actually asks what the "universe" means before trying to explain what it is
Minute Physics doesn't get as many updates as it used to these days, but when it does, they're usually quite good.The latest video aims to explain everything, that is to say, the universe, not a small undertaking in one minute. Which is probably why the video is close to three minutes.
Obviously, you're not going to get any amazingly revelatory answers in that short a time, but you may end up with a better understanding of what the universe is, at least as a concept.
Everyone knows "about" the universe, but much like all the other things we just "know" about, no one actually spends any time thinking about what "the universe" means in the first place.
In the simplest of terms, the universe is all that exists, now, in the past or in the future. Of course, that doesn't explain what it means to "exist" or what time is and so on and so forth.