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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

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.

See Examples For:

Many of these organisms are capable of surviving under extreme conditions, including very high temperatures and strongly acidic or alkaline environments.

From Science Daily ● Aug. 12, 2026

According to the researchers, this represents the first use of their alkaline thermal treatment method to overcome all three problems at once.

From Science Daily ● Jul. 31, 2026

Despite its vivid blue appearance, the water at the quarry - dubbed the Blue Lagoon - is highly alkaline and potentially harmful, with a pH level comparable to bleach.

From BBC ● May 28, 2026

“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

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

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