absurdness vs meaninglessness

absurdness and meaninglessness both are nouns.

Word	Noun	Adjective	Verb	Adverb
absurdness	Yes	No	No	No
meaninglessness	Yes	No	No	No

As nouns, meaninglessness is a hypernym of absurdness; that is, meaninglessness is a word with a broader meaning than absurdness:

Other hypernyms of absurdness include bunk, hokum, nonsense, nonsensicality.

absurdness (noun)	meaninglessness (noun)
a message whose content is at variance with reason	the quality of having no value or significance
	a message that seems to convey no meaning