slippage

(countable, uncountable) The act of slipping, especially from a secure location.
(countable, uncountable) The amount by which something has slipped.
(countable, uncountable) A lessening of performance or achievement.
(countable, uncountable) A decrease in motion, or in the power of a mechanical system, due to slipping.
(countable, uncountable) The difference between estimated and actual transaction costs.
(countable, uncountable) Movement of earth on a slope, a landslip.