plummet
/ˈplʌmɪt; `plʌmɪt/ n
1 (weight attached to a) plumb-line 测深锤; 铅锤; 铅垂线.
2 weight attached to a fishing-line to keep the float upright （钓丝上的）铅坠, 坠子（用以使鱼漂竖起）. plummet, v [I, Ipr, Ip]
fall steeply or rapidly 大坡度或快速落下
House prices have plummeted in this area. 此地房价大跌.
Pieces of rock plummeted down the mountainside to the ground below. 岩石一块块顺著山的陡坡滚落到地面.