SHOW UP

{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).