The substance in which another substance dissolves is called the solvent.

Here's a breakdown:

* Solvent: The substance that dissolves the solute. It's typically a liquid, but can also be a gas or solid.

* Solute: The substance that gets dissolved.

* Solution: The uniform mixture formed when the solute dissolves in the solvent.

For example:

* In a saltwater solution, water is the solvent and salt is the solute.

* In a sugar-water solution, water is the solvent and sugar is the solute.

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