roominess vs airiness

roominess and airiness both are nouns.

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

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

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

Other hyponyms of roominess include seating capacity.

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