insoluble

Imagine putting a powder into water and stirring, but it still stays there instead of disappearing into the liquid. That's what it means for something to be insoluble. It describes a substance that does not dissolve in another substance, unlike sugar in tea or salt in water.

Think of sand at the beach. You can swirl it around in water, but it does not disappear; it stays separate. Sand is insoluble in water. The term often comes up in science class when talking about materials and liquids, but you might also hear it used metaphorically to describe a problem with no solution or no clear answer, such as an "insoluble conflict."

The word "insoluble" describes something that cannot be dissolved in a particular solvent, usually a liquid. Dissolving happens when one substance spreads evenly through another, as sugar does in water. But some substances do not do that and remain separate.

This idea is most common in chemistry. For example, sand is insoluble in water; it will remain as visible particles no matter how much you stir. Many powders, minerals, or compounds are described this way when they do not dissolve in a given liquid. A chemist might also say that a substance is insoluble only under certain conditions, such as at a particular temperature.

However, "insoluble" is not limited to science. We also use it figuratively to describe problems that seem impossible to solve. A long-standing feud between families could be described as an "insoluble conflict," meaning there is no clear way to end it. A deep mystery or a very hard puzzle might also be called insoluble.

So, whether you are talking about a substance in a lab or a problem in everyday life, something that is insoluble either does not dissolve or cannot be solved.