hydroxide

noun

hy·​drox·​ide hī-ˈdräk-ˌsīd How to pronounce hydroxide (audio)
1
: the monovalent anion OH− consisting of one atom of hydrogen and one of oxygen

called also hydroxide ion

2
: an ionic compound of hydroxide with an element or group

Examples of hydroxide in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Water always contains a small number of hydroxide ions, and turning one into a hydroxyl radical requires stripping away an electron. — Jacek Krywko, ArsTechnica, 15 Oct. 2026 Fluorine is then released into the water as fluoride ions, while hydroxyl radicals and hydroxide ions help sever carbon-carbon bonds in the remaining molecular chains. — Alexandra Harrell, Footwear News, 14 Oct. 2026 Black Giant will supply lithium carbonate, while Project Lonestar will produce lithium hydroxide. — Georgina Jedikovska, Interesting Engineering, 13 Oct. 2026 Magnesium ions react with hydroxide ions at the narrow boundary between the two streams, producing solid magnesium hydroxide. — New Atlas, 27 July 2026 See All Example Sentences for hydroxide

Word History

Etymology

International Scientific Vocabulary

First Known Use

1851, in the meaning defined at sense 1

Time Traveler
The first known use of hydroxide was in 1851

Phrases Containing hydroxide

Rhymes for hydroxide

See All Rhymes for hydroxide

Browse Nearby Words

hydroxamic acid
hydroxide
hydroximino-
See all Nearby Words

Cite this Entry

“Hydroxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydroxide. Accessed 19 Oct. 2026.

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Kids Definition

hydroxide

noun
hy·​drox·​ide hī-ˈdräk-ˌsīd How to pronounce hydroxide (audio)
: a negatively charged ion consisting of one atom of oxygen and one atom of hydrogen

Medical Definition

hydroxide

noun
hy·​drox·​ide hī-ˈdräk-ˌsīd How to pronounce hydroxide (audio)
1
: the monovalent anion OH− consisting of one atom of hydrogen and one of oxygen

called also hydroxide ion

2
: an ionic compound of hydroxide with an element or group

More from Merriam-Webster on hydroxide

Britannica.com: Encyclopedia article about hydroxide

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