# alkaline

/ˈæɫkəˌɫaɪn/ (US) · /ˈælkəlˌaɪn/ (UK) · CEFR C1 · Adjective

Source: https://englishreference.com/word/alkaline
Updated: 2026-05-07

## Definition

having a pH level higher than 7. You use this to describe substances that are the opposite of acidic, like baking soda or soap.

For teachers: having a pH value greater than 7; possessing the properties of an alkali. Often used to describe chemical solutions or soil conditions that can neutralise acids.

## Examples

- The soil in this garden is naturally alkaline.
- Farmers often add lime to their fields to make the soil more alkaline for certain crops.
- The chemist monitored the solution carefully, adding small amounts of base until the mixture reached an alkaline state suitable for the next phase of the reaction.

## Usage notes

- Often used in technical or scientific contexts; frequently contrasted with 'acidic'.

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