Hypersolvus is a fancy word that scientists use to describe a mixture of two things, like salt and water, where there is more of one thing than the other and they are completely mixed together.
Imagine you have a bucket of water and you want to put some sugar in it. If you keep adding sugar to the water, eventually you will reach a point where the water can't dissolve any more sugar. This point is called "saturated". But if you keep adding more sugar, the water will become "hypersolvus" - which means there is more sugar than the water can normally hold, and they are totally mixed together.
So in simpler terms, hypersolvus is like when you pour too much sugar in your cup of tea and it won't dissolve anymore, but you keep stirring and stirring until it does dissolve and now it's super sweet - that's what hypersolvus means!