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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  
/ ălkə-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.

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

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

The rhenium component helped hydrogen attach to and release from the catalyst surface, while the molybdenum sped up the splitting of water in the alkaline electrolyte.

From Science Daily • May 18, 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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