'Horizontality' definitions:

Definition of 'horizontality'

(from WordNet)
noun
The quality of being parallel to the horizon; "houses with a pronounced horizontality"

Definition of 'Horizontality'

From: GCIDE
  • Horizontality \Hor`i*zon*tal"i*ty\, n. [Cf. F. horizontalit['e].] The state or quality of being horizontal. --Kirwan. [1913 Webster]