Eavesdrop (verb)

To listen secretly to a conversation without the speakers' knowledge.

Origin:

From the old english word "eavesdroppian" meaning "to listen secretly".

Examples:

1. He was caught trying to eavesdrop on the private conversation.
2. She was able to eavesdrop on the meeting by hiding outside the door.
3. The teenager tried to eavesdrop on his parents' phone call.
4. The detective used a hidden microphone to eavesdrop on the suspects.
5. The journalist was able to eavesdrop on the politician's secret meeting.