folly vs imbecility

folly and imbecility both are nouns.

Word	Noun	Adjective	Verb	Adverb
folly	Yes	No	No	No
imbecility	Yes	No	No	No

As nouns, folly and imbecility are synonyms defined as:

Other synonyms of folly include betise, foolishness, stupidity.

folly (noun)	imbecility (noun)
foolish or senseless behavior	a stupid mistake
a stupid mistake	retardation more severe than a moron but not as severe as an idiot
the trait of acting stupidly or rashly
the quality of being rash and foolish