wittiness vs irony

wittiness and irony both are nouns.

Word	Noun	Adjective	Verb	Adverb
wittiness	Yes	No	No	No
irony	Yes	No	No	No

As nouns, irony is a hyponym of wittiness; that is, irony is a word with a more specific, narrower meaning than wittiness:

wittiness: a message whose ingenuity or verbal skill or incongruity has the power to evoke laughter
irony: witty language used to convey insults or scorn

wittiness (noun)	irony (noun)
The quality of being clever, amusingly ingenious.	incongruity between what might be expected and what actually occurs
a message whose ingenuity or verbal skill or incongruity has the power to evoke laughter	a trope that involves incongruity between what is expected and what occurs
	witty language used to convey insults or scorn