slippage
n. C / Un. the act of sliding or moving out of place, or a small loss in progress or value. In trading and cryptocurrency, slippage is the gap between the price you expect on a trade and the price it actually executes at, which widens when the market is volatile or thinly traded.
n. the act or instance of sliding out of position, or a gradual decline in performance, standards, or value. In trading, slippage is the difference between an order's expected execution price and its actual fill price, driven by volatility and low liquidity.
The project suffered from some slippage in the schedule.
The manager noted a slight slippage in quality control after the new software system was installed.
Market analysts warned that the currency's recent slippage against the dollar could trigger inflationary pressures across the domestic manufacturing sector.
From the verb slip plus -age: the amount by which a price slips between order and execution.