# waterproof

/ˈwɔtɝˌpɹuf/ (US) · /wˈɔːtəpɹˌuːf/ (UK)

Source: https://englishreference.com/word/waterproof
Updated: 2026-06-20

## Senses

### 1. impervious to water

adjective · CEFR B1

made of a material that does not let water pass through it.

For teachers: impervious to water; specifically describing materials or objects designed to prevent the penetration of liquid water.

- You should wear a waterproof jacket because the weather report predicts heavy rain.
- The new smartphone model is rated as fully waterproof, allowing it to be submerged in shallow water for up to thirty minutes without damage.

Usage: Often used to describe clothing, electronics, or building materials.

### 2. incapable of failing

adjective · CEFR C2 · Literary

something that is so well-planned or strong that it cannot fail or be attacked.

For teachers: metaphorically unassailable or incapable of being defeated or found false.

- The lawyer presented a waterproof argument that the jury couldn't disagree with.
- The prosecution spent months constructing a waterproof case, ensuring that every piece of forensic evidence was corroborated by multiple witnesses.

### 3. to make water-resistant

verb · CEFR B2

to treat something with a special substance so that water cannot get in.

For teachers: to treat a surface or object with a substance to render it impervious to water. Transitive use requiring a direct object.

- I need to waterproof my hiking boots before we go on the camping trip.
- The contractor recommended that we waterproof the basement walls to prevent moisture from seeping through the foundation during the spring thaw.

### 4. a rain coat

noun · CEFR B2 · British English

a coat or piece of clothing made from material that keeps you dry.

For teachers: a garment, such as a raincoat or mackintosh, made from water-resistant material.

- Don't forget to pack your waterproof if you are going walking in the mountains.
- He pulled his yellow waterproof tight against the gale, though the salt spray still found its way past his collar.

## Examples

- This jacket is waterproof and keeps you dry.
- She bought a waterproof backpack for her hiking trip.
- The new smartphone features a waterproof design that protects internal components from accidental submersion in shallow water.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.