不及物动词

1. （数量、比率或价格）骤然下跌，暴跌
If an amount, rate, or price plummets, it decreases quickly by a large amount.

2. （通常指从高处）快速落下，陡直掉下
If someone or something plummets, they fall very fast towards the ground, usually from a great height.

1. the metal bob of a plumb line

Synonym: plumb bobplumb