precipitous (adj.)

1640s, "rash, done with excessive or undue haste" (a sense now obsolete), also "rushing headlong, violently hurried," from obsolete French precipiteux (16c.), from Vulgar Latin *praecipitosus, from praecipitare "to throw or dive headlong; be hasty" (see precipitation). Meaning "high and steep" is from 1806. Related: Precipitously; precipitousness.