Rochester Shake
An idiosyncratic tendency characterized by the combination of the rapid horizontal shaking of one's head and the simultaneous twitching of one or both hands. The Rochester Shake is used almost exclusively when one is expressing disagreement or displeasure, however in combination with a dropped jaw, it can also express exasperation.
When someone contested the fact that George "has never done a lab", George defended his statement while engaging in a classic Rochester Shake.