waterproofness

noun

1. (uncountable)The property of being waterproof.

   “In the fabric section, a textile twisting and tearing machine and a "Lissajou curve" [sic] abrader (covering a complete area in overlapping curves) are supplemented by apparatus for evaluating waterproofness, fibre diameter and light-fastness.”

   “To find the best rain jacket, we tested everything from waterproofness and breathability to fit, feel and packability.”