Universe

A universe is a large cosmic web containing planets, moons, minor planets, stars, clusters, and galaxies. Our universe contains huge clusters of galaxies called hyperclusters, alongside voids with little to no galaxies, and has 4 dimensions (3 of space and 1 of time). It is constantly expanding.

Containers
As mentioned above, the local universe is finite but it's constantly expanding and growing in size. This phonemenon is unexplained by there being one universe. One idea, and perhaps the most likely one, is that Universes are regular expanding bubbles inside the vacuum.

But it could also be that universes are contained on a 5-dimensional realm known as the Multiverse. Multiverses are out of this wiki's scope, but you can find about them on the affiliated wikis who decided to focus on large verses.

Etymology
The word universe derives from the Old French word univers, which in turn derives from the Latin word universum.