Relevance is how much something actually belongs to the matter in front of you. If a fact, a question, or a story has relevance, it is not only interesting — it touches what people are talking about or trying to decide. Teachers, judges, and people in meetings ask about the relevance of a point, meaning “does this help with the real question?” A thing can be true and still have little relevance. In easy talk you more often hear that doesn’t matter here or that’s not related. Though actually, people also stretch the word: they say a class has no relevance to real life, meaning it does not feel useful, not that it fails a logic test. So the tidy school meaning is “linked to this subject,” and the looser everyday meaning is “useful or worth bringing up.”