precipitous
adjective uk/prɪˈsɪp.ɪ.təs/ us/priːˈsɪp.ə.t̬əs/
陡峭的，陡峻的
If a slope is precipitous, it is very steep.
a precipitous mountain path 陡峭的山路
骤然的，急剧的
If a reduction or increase is precipitous, it is fast or great.
Over the past 18 months, there has been a precipitous fall in car sales. 在过去的18个月内汽车销量暴跌。