waterproofness

This term describes a technical property of a material, typically used in industrial, textile, or outdoor gear contexts. It focuses on the absolute capacity of a surface to repel water or prevent leakage, rather than just resisting moisture for a short period.

Because it describes an inherent quality or state, the word is treated as an uncountable mass noun. It is rarely used in plural form, as the property of being waterproof is viewed as a singular characteristic of a product or material.