slippage
noun [ U ] uk/ˈslɪp.ɪdʒ/ us/ˈslɪp.ɪdʒ/
减少，降低
a reduction in the rate, amount, or standard of something
The party leader is said to be concerned at the slippage (= loss of popularity) in the recent opinion polls. 据称，该党领导人对最近民意测验中支持率的下滑感到忧心忡忡。
未能按时发生（或完成）
a failure to happen or finish on time
the slippage of the book's publication date 这本书出版的推迟