Causticity

Causticity is that sharp and corroding quality, which many substances possess, such as the mineral acids, especially when concentrated, alkalies fixed and volatile, quicklime, arsenic, corrosive sublimate, lunar crystals, butter of antimony, and even most other salts with metallic bases.

Some years ago, we read in a U.S. trade paper a method for determining causticity of bottle-washing solution when foil labels are contained on the bottles undergoing cleansing treatment.

1996, Christopher J. Biermann, Handbook of Pulping and Papermaking, Academic Press, 3.8 Kraft Pulping, p. 89, https://books.google.ca/books?id=sfZfyEmqs_AC&printsec=frontcover#v=onepage&q&f=false Causticity is the ratio of NaOH to active alkali (as always both chemicals are on an Na₂O basis), expressed as a percentage.

[…] one in whom a discreet causticity went along with a manner less genial than polite […]

He had not, he remarked with crushing causticity to one of his ministers, liberated France ‘to worry about the macaroni ration’.