waterproof

water|proof /w'ɔːtə^rpruːf/ (waterproofs waterproofing waterproofed)
1 [ADJ]
Something which is waterproof does not let water pass through it.
Take waterproof clothing-Orkney weather is unpredictable...
2 [N-COUNT] usu pl
Waterproofs are items of clothing which do not let water in. (mainly BRIT)
For staying dry you'll want nice lightweight waterproofs to wear over your leathers.
3 [VERB] usu passive, be V-ed
If something is waterproofed, it is treated so that water cannot pass through it or damage it.
The whole boat has been totally waterproofed...