1. listen quietly, without contributing to the conversation;
2. listen without the speaker's knowledge; - Example: "the jealous man was eavesdropping on his wife's conversations" [syn: listen in, eavesdrop]
WordNet (r) 3.0 (2006):
listen in
v 1: listen quietly, without contributing to the conversation
2: listen without the speaker's knowledge; "the jealous man was
eavesdropping on his wife's conversations" [syn: listen in,
eavesdrop]