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

But even alkaline garden soil may become acidic over time as a result of environmental factors, such as acid rain, or the overuse of synthetic fertilizers and other soil amendments. — Lauren Landers, Better Homes & Gardens, 5 Sep. 2026

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

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