# sulfate

/ˈsəɫˌfeɪt/ (US) · /sˈʌlfeɪt/ (UK)

Source: https://englishreference.com/word/sulfate
Updated: 2026-08-27

## Senses

### 1. chemical compound

noun · CEFR C1 · Technical

a chemical substance that contains sulfur and oxygen, often found in nature or used in products like shampoo.

For teachers: any salt or ester of sulfuric acid, characterized by the presence of the SO₄²⁻ group.

- Many people prefer to buy shampoo that does not contain any sulfate.
- The laboratory analysis confirmed high concentrations of magnesium sulfate in the soil samples collected from the industrial site.

### 2. to treat with chemicals

verb · CEFR C2 · Technical · American English

to treat a material with sulfuric acid or a similar chemical.

For teachers: to treat or combine a substance with sulfuric acid, a sulfate, or sulfur dioxide.

- The manufacturer decided to sulfate the wood to make it more durable.
- Engineers must carefully monitor the temperature when they sulfate the organic compounds to ensure the reaction remains stable.

Usage: This verb is transitive and requires a direct object.

### 3. battery buildup

verb · CEFR C2 · Technical

when lead sulfate builds up inside a battery, which can stop it from working.

For teachers: to accumulate a deposit of lead sulfate on the plates of a lead-acid battery, typically reducing its efficiency.

- If you leave the car battery empty for too long, the plates will sulfate.
- The technician explained that the battery failed because the internal plates had begun to sulfate after months of deep discharge.

Usage: Often used in the context of battery maintenance and failure.

## Examples

- This shampoo is free from sulfates.
- Farmers often apply magnesium sulfate to the soil to help crops grow better when minerals are low.
- The concentration of particulate sulfate in the atmosphere can significantly influence cloud formation and contribute to the acidification of rainwater in industrial regions.

---

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.