overhear
To accidentally hear a conversation not meant for you.
To overhear means to accidentally hear something that others are saying, usually when they don't know you're listening or don't realize you can hear them. Unlike eavesdropping, which means deliberately trying to listen to private conversations, overhearing just happens. You might overhear your teacher talking to another teacher in the hallway, or overhear your parents discussing weekend plans from the next room.
Sometimes what you overhear is meant to be private, and sometimes it's just casual conversation that wasn't directed at you. You might overhear classmates planning a surprise party, or overhear someone mention your name while talking to a friend. The key is that you weren't part of the conversation and weren't supposed to be listening, but the words reached your ears anyway.
People often think about what to do after overhearing something. If you overhear something private or personal, it’s respectful to keep it to yourself and not spread it around. But if you overhear important information, like someone planning something dangerous, telling a trusted adult might be necessary.