Proof against penetration or permeation by water; impervious to water; as, a waterproof garment; a waterproof roof.
- Impervious to or unaffected by water.
- Made of or coated or treated with rubber, plastic, or a sealing agent to prevent penetration by water.
- A material or fabric that is impervious to water.
- Chiefly British A raincoat or other such outer garment.
- To make impervious to water.