when a politician straight-faced and blatantly contradicts something they said only a short time before, denies doing so, and it is on tape so you can clearly see what they did. Also known as a "lie".
Romney said the sky is blue on tuesday. On wednesday he said the sky is never blue and he never claimed it was blue.
He did it with a straight face.
We hit rewind and saw exactly what he said both times, yet he denied contradicting himself. It was an etch-a-sketch moment for that politician.