mischievousness vs misbehaviour

mischievousness and misbehaviour both are nouns.

Word	Noun	Adjective	Verb	Adverb
mischievousness	Yes	No	No	No
misbehaviour	Yes	No	No	No

As nouns, misbehaviour is a hypernym of mischievousness; that is, misbehaviour is a word with a broader meaning than mischievousness:

mischievousness: reckless or malicious behavior that causes discomfort or annoyance in others
misbehaviour: improper or wicked or immoral behavior

Other hypernyms of mischievousness include misbehavior, misdeed.

mischievousness (noun)	misbehaviour (noun)
reckless or malicious behavior that causes discomfort or annoyance in others	improper or wicked or immoral behavior
an attribute of mischievous children
the trait of behaving like an imp