A supercluster is a large assembly of thousands or tens of thousands of galaxies which form some of the largest-scale structures in our universe. They contain smaller groups called galaxy clusters and galaxy groups, which together contain galaxies of every type - it's very common to see lots of elliptical and spiral galaxies together in a supercluster.

Normally, superclusters are the largest structures in the universe which are gravitationally bound. Many superclusters have enough mass to keep themselves together against the accelerating force of dark energy.