Erroneous Trade

Sometimes called a "fat finger" trade. These are the times when a stock trader types in 2,000,000 shares when she really meant to type in 2,000 shares. The zeros just flew out of nowhere.

To avoid people backing out of otherwise legitimate trades that lost money by retroactively claiming they were "erroneous," exchanges and regulators have clear rules about what will constitute an erroneous trade. Among the guidelines: You have to make a claim within a half hour of executing the trade. Wait longer than that, and the official term issued by FINRA and NASDAQ is "tough noogie."

If a claim is made, an authority figure (stately, plump, gray-haired) will review the trade and make a ruling as to whether it was actually erroneous and what should be done in response. Meanwhile, the trader in question is sweating like a heart attack patient stuck in a sauna, wondering if maybe she'll have to start looking into getting a real estate sales license. Or worse.