Immaterial means not important or not relevant to what matters. When a detective solves a case, the color of the suspect's shoes is usually immaterial to the investigation. It doesn't affect the outcome. When you're trying to convince your parents to let you get a pet, the fact that your neighbor has three cats is immaterial: it has nothing to do with whether you're responsible enough to care for an animal.

In philosophy and science, something immaterial has no physical form, like thoughts, emotions, or spirits. But in everyday conversation, when someone says “That's immaterial,” they mean “That doesn't matter” or “That's beside the point.”

You might hear a lawyer object in court that a question is immaterial to the case, meaning it won't help determine the truth of what happened. Or a teacher might tell students that whether they liked a book is immaterial when analyzing what literary techniques the author used. The word helps us cut through distractions and focus on what actually matters in the question at hand.