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.
Aluminum hydroxide is the most commonly used. — Dr. John De Jong, Boston Herald, 31 May 2026 The rover dropped samples into a small cup of tetramethylammonium hydroxide, or TMAH. — Ashley Strickland, CNN Money, 24 Apr. 2026 The facility is the first of its kind in North America, converting spodumene ore directly into battery-grade lithium hydroxide. — John Pacenti, USA Today, 15 Apr. 2026 Then, a simple water-splitting reaction at the auxiliary electrode generates hydroxide, which combines with the lithium to produce lithium hydroxide. — New Atlas, 31 Dec. 2025 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 7 Jul. 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

Nglish: Translation of hydroxide for Spanish Speakers

Britannica.com: Encyclopedia article about hydroxide

Last Updated: - Updated example sentences
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