falseness vs irreality

falseness and irreality both are nouns.

Word	Noun	Adjective	Verb	Adverb
falseness	Yes	No	No	No
irreality	Yes	No	No	No

As nouns, irreality is a hypernym of falseness; that is, irreality is a word with a broader meaning than falseness:

falseness: the state of being false or untrue
irreality: the state of being insubstantial or imaginary; not existing objectively or in fact

Other hypernyms of falseness include unreality.

falseness (noun)	irreality (noun)
the quality of not being open or truthful; deceitful or hypocritical	the state of being insubstantial or imaginary; not existing objectively or in fact
unfaithfulness by virtue of being unreliable or treacherous
the state of being false or untrue