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alkaline

American  
[al-kuh-lahyn, -lin] / ˈæl kəˌlaɪn, -lɪn /

adjective

Chemistry.

  1. of or like an alkali.

  2. containing an alkali.

  3. having the properties of an alkali.

  4. having a pH value greater than 7.

alkaline British  
/ ˈælkəˌlaɪn /

adjective

  1. having the properties of or containing an alkali

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
alkaline Scientific  
/ ăl′kə-lĭn,-līn′ /

  1. Capable of neutralizing an acid. Bases are alkaline.

  2. Relating to an alkali compound.

  3. Having a pH greater than 7.

  4. Having a relatively low concentration of hydrogen ions.

Etymology

Origin of alkaline

First recorded in 1670–80; alkal(i) + -ine 1

Vocabulary lists containing alkaline

Chemistry - High School

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Chemistry - Middle School

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“When the Emperor Was Divine” takes place in Utah, in “a city of tar-paper barracks behind a barbed-wire fence on a dusty alkaline plain.”

From The Wall Street Journal • Feb. 17, 2026

The results were all over the map, but at least one finding was consistent: All but one of the properties showed evidence of high pH, or increased alkalinity, likely because ash is highly alkaline.

From Los Angeles Times • Apr. 24, 2025

The liquid is believed to be a type of home-made chilli spray with no strong acid or alkaline ingredients, police added.

From BBC • Feb. 18, 2025

This charge allows them to work throughout the body in chemical reactions that maintain normal brain functioning, balance fluids inside and outside of body cells and even balance how acidic or alkaline your blood is.

From Salon • Jan. 21, 2025

When the soil is too alkaline, which can be thought of as being too sweet, you need to add sulfur.

From "Counting by 7s" by Holly Goldberg Sloan

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.