ELI5: Explain Like I'm 5

Solubility

Solubility means something can be dissolved in liquid. For example, sugar will dissolve in water if you stir it. When something can dissolve in a liquid, it is called "soluble." If it can't, it is called "insoluble." So, when something is soluble, it means it can dissolve in liquid and when something is insoluble, it means it will not dissolve in liquid.