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 higher the acidity (pH less than six), the bluer your blooms, while more alkaline soil (pH greater than seven) typically results in pinkish flowers. —Patricia Shannon, Southern Living, 9 May 2026

Success is dependent on being planted in sunny locations with moist, well-drained, and neutral to slightly alkaline pH soils. —Emily Leahy, Hartford Courant, 3 May 2026

Baking soda is alkaline, so washing herbs in baking soda destroys vitamin C. —Merve Ceylan, Health, 30 Apr. 2026

The baths here contain either ground water from Mount Fuji, consisting of snowmelt from the summit filtered through layers of volcanic rock, or naturally alkaline onsen spring waters that emerge from underground at high temperatures. —Condé Nast, Condé Nast Traveler, 23 Apr. 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