A slippage that occurs when an order is executed at a less favorable (lower for a sell order, and higher for a buy order) than the price requested by a trader. For example, if a trader posted an order to buy at $15.1050, and execution has taken place at $15.1054, a positive slippage of (15.1054- 15.1050 = 0.004, or 4 pips) would form to the disadvantage of the trader.

The opposite scenario is a positive slippage.