hearsay
Information someone heard from others, not seen themselves.
Hearsay is information you heard from someone else but didn't witness yourself. If your friend tells you that another student broke a rule at school, but you didn't see it happen, that's hearsay. You're repeating something based on what someone told you, not on what you actually know firsthand.
Hearsay is often unreliable. Information can get distorted as it passes from person to person, like the telephone game where a message changes completely by the time it reaches the last person.
This matters especially in courtrooms, where judges usually don't allow hearsay as evidence. If a witness didn't see or hear something directly, their testimony about it isn't considered trustworthy enough for making important legal decisions. A detective can't testify about what a neighbor told them someone else said. They need people who actually saw what happened.
In everyday life, being careful about hearsay helps you avoid spreading rumors or false information. When someone starts a sentence with “I heard that...” or “Someone told me...”, you're probably hearing hearsay, and it's worth finding out if it's actually true before believing or repeating it.