The dictionary defines a mirror as a reflecting surface, something that gives a minutely faithful representation, image, or idea of something else.
When used in the psychological sense, mirroring is the replication of another individual’s nonverbal signals. We mirror others’ expressions and gestures when we like them and feel connected to them, usually without anyone noticing. Imagine you are talking to a friend and he leans forward and smiles; without consciously realizing what you are doing, you will likely smile and lean forward as well.
Mirroring creates rapport between people. Most psychologists agree the person who is mirroring the behavior is demonstrating empathy: the person who is mirroring feels a connection to the other person when making the same expressions or gestures and they person being mirrored tends to believe the other individual shares their thoughts and feelings.