precipitousness vs precipitance

precipitousness and precipitance both are nouns.

Word	Noun	Adjective	Verb	Adverb
precipitousness	Yes	No	No	No
precipitance	Yes	No	No	No

As nouns, precipitousness and precipitance are synonyms defined as:

precipitousness and precipitance: the quality of happening with headlong haste or without warning

Other synonyms of precipitousness include abruptness, precipitancy, precipitateness, suddenness.

precipitousness (noun)	precipitance (noun)
the property possessed by a slope that is very steep	the quality of happening with headlong haste or without warning
the quality of happening with headlong haste or without warning