Noun

(uncountable) The quality of being vast.

* , chapter=5

, title= The Mirror and the Lamp , passage=He was thinking; but the glory of the song, the swell from the great organ, the clustered lights, […], the height and vastness of this noble fane, its antiquity and its strength—all these things seemed to have their part as causes of the thrilling emotion that accompanied his thoughts.}}

(countable) Something vast.