perpendicularity (uncountable)

1. The condition of being perpendicular.
   • 1945 August 17, George Orwell [pseudonym; Eric Arthur Blair], chapter 6, in Animal Farm: A Fairy Story, London: Secker & Warburg, OCLC 3655473 ↗:

     In their spare moments the animals would walk round and round the half-finished mill, admiring the strength and perpendicularity of its walls and marvelling that they should ever have been able to build anything so imposing.