idiom · a crafty stratagem involving vanishing and leaving a facade behind to deceive others

敌人使了个金蝉脱壳之计，趁夜色从包围圈中溜走了。

idiom · the literal process of a cicada shedding its carapace

自然课上，老师带我们观察了金蝉脱壳的奇妙过程。