Solvent:This is the substance in a solution that does the dissolving, like water in our lemonade example.
Solute:This is the substance that gets dissolved in a solution, like sugar in our lemonade analogy.
Saturation:This term refers to the point at which no more solute can be dissolved into a solvent at a given temperature. If you keep adding sugar to your lemonade and it stops dissolving, your solution has reached saturation.