a plan or course of action that is ready to be used in an emergency if other things fail 应变计划；退路◆Each stage of the plan has a fallback. 计划的每一阶段都有应变安排。◆We need a fallback position if they don't accept our offer. 如果他们不接受我们的报价，我们就需要有一个应变方案。➡fall back on sth at fall verb
a reduction or decrease in sth 减少；下降◆a fallback in energy prices 能源价格的回落SYNfall ➡fall back at fall verb