precipice vs drop-off

precipice and drop-off both are nouns.

Word	Noun	Adjective	Verb	Adverb
precipice	Yes	No	No	No
drop-off	Yes	No	No	No

As nouns, drop-off is a hypernym of precipice; that is, drop-off is a word with a broader meaning than precipice:

Other hypernyms of precipice include cliff, drop.

precipice (noun)	drop-off (noun)
a very steep cliff	a change downward
	a steep high face of rock
	a noticeable deterioration in performance or quality