alkaline

adjective

al·​ka·​line ˈal-kə-lən  -ˌlīn 

: of, relating to, containing, or having the properties of an alkali or alkali metal : basic

especially, of a solution : having a pH of more than 7

alkalinity

ˌal-kə-ˈli-nə-tē 

noun

Examples of alkaline in a Sentence

Recent Examples on the Web

The challenge is that the hydrogen evolution reaction is slower in alkaline environments, increasing the need for catalysts that can deliver high activity without rapidly losing performance. — Bojan Stojkovski, Interesting Engineering, 22 Aug. 2026

Rinsing helps strip away the alkaline preservative film that often coats synthetic braiding hair. — Ayren Jackson-Cannady, Allure, 20 Aug. 2026

In short, plain water isn’t lacking anything that alkaline water provides for the average healthy person. — Lauren Panoff, Verywell Health, 12 Aug. 2026

Fresh concrete is alkaline enough to shield the metal from rust, but carbonation gradually lowers its pH and weakens that protection. — Sam MacDonald, Scientific American, 11 July 2026

Word History

First Known Use

1682, in the meaning defined above

Phrases Containing alkaline

• alkaline battery
• alkaline earth metal
• alkaline hydrolysis
• alkaline phosphatase

Rhymes for alkaline

• andesine
• anodyne
• anticline
• arginine
• asinine
• benzidine
• borderline
• byzantine
• calamine
• caroline
• centerline
• chloroquine

Kids Definition

alkaline

adjective

al·​ka·​line ˈal-kə-lən  -ˌlīn 

: of, relating to, or having the characteristics of an alkali : basic

alkalinity

ˌal-kə-ˈlin-ət-ē 

noun

Medical Definition

alkaline

adjective

al·​ka·​line ˈal-kə-lən  -ˌlīn 

: of, relating to, containing, or having the properties of an alkali or alkali metal : basic

especially, of a solution : having a pH of more than 7

alkalinity

ˌal-kə-ˈlin-ət-ē 

noun

plural alkalinities