significance vs insignificant

significance is a noun but insignificant is not a noun.

Word	Noun	Adjective	Verb	Adverb
significance	Yes	No	No	No
insignificant	No	Yes	No	No

significance (noun)	insignificant (noun)
the quality of being significant
a meaning that is not expressly stated but can be inferred
the message that is intended or expressed or signified

significance (adjective)	insignificant (adjective)
	devoid of importance, meaning, or force
	signifying nothing
	of little importance or influence or power; of minor status
	small and unimpressive