airiness vs roominess

airiness and roominess both are nouns.

Word	Noun	Adjective	Verb	Adverb
airiness	Yes	No	No	No
roominess	Yes	No	No	No

As nouns, roominess is a hypernym of airiness; that is, roominess is a word with a broader meaning than airiness:

airiness: the property of something spacious and abounding in fresh air
roominess: spatial largeness and extensiveness (especially inside a building)

Other hypernyms of airiness include capaciousness, commodiousness, spaciousness.

airiness (noun)	roominess (noun)
the property of something weightless and insubstantial	spatial largeness and extensiveness (especially inside a building)
the property of something spacious and abounding in fresh air	intellectual breadth
lightness in movement or manner