I. wa ‧ ter ‧ proof 1 /ˈwɔːtəpruːf $ ˈwɒːtər-, ˈwɑː-/ BrE AmE adjective
not allowing water to enter:
a waterproof jacket
waterproof adhesive
Rub the wax in to make the shoe waterproof.
—waterproof verb [transitive] :
Plastic sheeting was used to waterproof the shed.
—waterproofed adjective [only before noun] :
a waterproofed sack
II. waterproof 2 BrE AmE noun [countable usually plural]
a jacket or coat that does not allow rain and water through it
waterproofs (=a waterproof jacket and trousers)