hydroxide

noun

hy·​drox·​ide hī-ˈdräk-ˌsīd 

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

Magnesium ions react with hydroxide ions at the narrow boundary between the two streams, producing solid magnesium hydroxide. — New Atlas, 27 July 2026

Reportedly, EVelution has signed agreements to source the raw cobalt hydroxide feedstock from the Democratic Republic of the Congo (DRC). — Mrigakshi Dixit, Interesting Engineering, 2 July 2026

Aluminum hydroxide is the most commonly used. — Dr. John De Jong, Boston Herald, 31 May 2026

Tesla is seeking to increase the domestic supply of battery-grade lithium hydroxide at the nearly $1 billion lithium refinery plant that began operating in late 2024. — Arcelia Martin, San Antonio Express-News, 27 Apr. 2026

Word History

Etymology

International Scientific Vocabulary

First Known Use

1851, in the meaning defined at sense 1

Phrases Containing hydroxide

• ammonium hydroxide
• calcium hydroxide
• magnesium hydroxide
• potassium hydroxide
• sodium hydroxide

Rhymes for hydroxide

• monoxide
• tetroxide

Kids Definition

hydroxide

noun

hy·​drox·​ide hī-ˈdräk-ˌsīd 

: 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 

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