v. 1. To make known the real truth about (someone). The man said he was a mind reader, but he was shown up as a fake. 2. To come or bring out; become or make easy to see. The detective put a chemical on the paper, and the fingertips showed up. This test shows up your weaknesses in arithmetic. 3. informal To come; appear. We had agreed to meet at the gym, but Larry didn't show up. Only five students showed up for the class meeting.
Compare: TURN UP 2 .