I. | ̷ ̷ ̷ ̷| ̷ ̷ adjective
Etymology: water + proof
: impervious to water: as
a. : covered or treated with a material (as a solution of rubber) to prevent permeation by water
b. : relating to or characterizing a machine or structure so constructed that a stream of water may be directed on it under specified conditions without the water entering
• wa·ter·proof·ness noun -es
II. noun
1. : a waterproof fabric
2. chiefly Britain : raincoat
III. transitive verb
: to make waterproof