ENGLISH
REFERENCE

alkaline

adj.
C1 Advanced US //ˈæɫkəˌɫaɪn// UK //ˈælkəlˌaɪn// al·ka·line

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

adj. 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.


SIMPLE

The soil in this garden is naturally alkaline.

CONTEXTUAL

Farmers often add lime to their fields to make the soil more alkaline for certain crops.

COMPLEX

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.

Synonyms
Antonyms
Origin

First attested in 1677. From alkali + -ine, ultimately from Arabic اَلْقِلْي (al-qily, “alkali, ashes of the saltwort”), related to قَلَى (qalā, “to roast in a pan, fry”).

Usage

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

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