or not
Usually a sarcastic comment made after somebody pitches an idea. Otherwise, it can be said when someone is really excited about an idea that you think is stupid.
Person 1: "We could go play DDR at my house." Person 2: "...Or not."
Person 1: "Hey, you guys! I'm so excited about object!!!" Person 2: "...Or not."
Person 1: "Hey, you guys! I'm so excited about object!!!" Person 2: "...Or not."
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