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Synonyms

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.

It has been estimated that a typical cremation has a footprint equivalent to about 320kg of carbon dioxide- Alkaline hydrolysis is found to result in the emission of seven times less CO2.

From BBC • Mar. 2, 2026

Alkaline materials such as limestone or olivine could be ground up or dissolved in water and then poured into the ocean from a ship.

From Science Magazine • Nov. 30, 2023

Alkaline water, for instance, has a higher-than-average pH value that makes it less acidic, but to prevent dehydration, medical professionals say that the amount of water you drink—not pH levels—is more hydrating.

From National Geographic • Sep. 14, 2023

DeLonge, who quit Blink in 2015 and was replaced by Matt Skiba of Alkaline Trio, revealed last year that he’d reunited with Hoppus and Barker amid Hoppus’ treatment for cancer.

From Los Angeles Times • Apr. 13, 2023

Alkaline remedies of every description, must be most carefully avoided, their use in every point of view being most mischievous when the phosphates are concerned.

From North American Medical and Surgical Journal, Vol. 2, No. 3, July, 1826 by Bache, Franklin

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.