All 3 Uses

precipitous
in
Into the Wild
(Edited)

He stayed there for ten days, until high winds forced him to seek refuge in a cave midway up the precipitous face of the bluff, where he remained for another ten days.
p. 36.1

precipitous = steep
Slopes rose precipitously from the water's edge, bearded in a gloom of hemlock and cedar and devil's club.
p. 136.6 *

precipitously = steeply
By August 19, he was dead. There has been a great deal of conjecture about what caused such a precipitous decline.
p. 189.9 *

precipitous = sudden

Definitions:

(1) (precipitous as in: a trail with a precipitous drop)
very steep
(2) (precipitous as in: a precipitous decision)
sudden
(3) (meaning too rare to warrant focus)
More rarely, precipitous may mean characterized by precipices (steep cliffs); or extremely steep.