precociousness vs precocity

precociousness and precocity both are nouns.

Word	Noun	Adjective	Verb	Adverb
precociousness	Yes	No	No	No
precocity	Yes	No	No	No

As nouns, precociousness and precocity are synonyms defined as:

precociousness and precocity: intelligence achieved far ahead of normal developmental schedules

precociousness (noun)	precocity (noun)
intelligence achieved far ahead of normal developmental schedules	intelligence achieved far ahead of normal developmental schedules