English Reference

Word

hydroxide

Phoneticshy·drox·ide

US/haɪˈdɹɑksaɪd/

UK/haɪdɹˈɒksaɪd/

Definition

n. a chemical compound that contains the group OH⁻. You often find this in cleaning products or when water reacts with certain metals.

n. a chemical compound containing the hydroxide ion, OH⁻. It is typically formed when a base reacts with water or when a metal reacts with water.

Examples

“Sodium hydroxide is a common ingredient in soap.”

“When aluminum reacts with water, it produces aluminum hydroxide and hydrogen gas.”

“The formation of magnesium hydroxide in the soil helps to neutralize acidic conditions, making the environment more hospitable for plant life.”

Examples

simple

“Sodium hydroxide is a common ingredient in soap.”

contextual

“When aluminum reacts with water, it produces aluminum hydroxide and hydrogen gas.”

complex

“The formation of magnesium hydroxide in the soil helps to neutralize acidic conditions, making the environment more hospitable for plant life.”

Real-World Examples

“Low concentrations of caustic soda (sodium hydroxide, NaOH) are more efficient than high doses for preparing organic waste for biogas production.”
Phys.org · 20 Aug 2026
“In this process, sodium hydroxide reacts with organic material under heat, triggering chemical reactions that produce hydrogen.”
ScienceDaily · 31 Jul 2026

Etymology

From hydro- + oxide.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Domain

Chemistry

This entry

Level
C1 · Advanced
Frequency
Occasional
Updated

Scan code

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English Reference