Used as an apathetic interjection, when one is asked a question, or asked to make a response to something you don't feel strongly about.
Person 1: Hey Man! How're you doing today?
Person 2: Eh.
Person 1: How bout them Cubs?
Person 2: Eh.
Person 1: (Pause) Dammit! Say something!
Person 2: Eh.
Person 2: Eh.
Person 1: How bout them Cubs?
Person 2: Eh.
Person 1: (Pause) Dammit! Say something!
Person 2: Eh.
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