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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:

Because the area near the anode tends to become acidic while the area near the cathode becomes alkaline, bringing these regions closer together and circulating the liquid helps counterbalance their effects.

From Science Daily ● Oct. 12, 2026

Those groups create chemically reactive sites, allowing the alkaline treatment to break down materials that would otherwise remain largely inert.

From Science Daily ● Jul. 31, 2026

Another is ocean alkalinity, in which alkaline rocks are dispersed in the sea to capture carbon and neutralize it in seawater.

From The Wall Street Journal ● Jun. 17, 2026

It is one of the only spas with natural, alkaline hot springs in L.A., so the water is just heavenly.

From Los Angeles Times ● May 15, 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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