iron oxide

noun

: any of several oxides of iron: such as
b
: the monoxide FeO of iron

Examples of iron oxide 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.
The acid in vinegar reacts with iron oxide and dissolves the rust. Brandee Gruener, Southern Living, 29 July 2025 The cabins’ deep red hue is down to a mix of iron oxide and fish blood. Phil Thomas, Travel + Leisure, 15 July 2025 This formula blends zinc oxide and iron oxide to block UVA and UVB rays, and can even help block out blue light. Alanna Martine Kilkeary, Glamour, 9 July 2025 Rust, which is a common form of iron oxide found here on Earth, also often has a reddish color. David Joffe, Space.com, 19 June 2025 See All Example Sentences for iron oxide

Word History

First Known Use

1790, in the meaning defined above

Time Traveler
The first known use of iron oxide was in 1790

Cite this Entry

“Iron oxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/iron%20oxide. Accessed 20 Aug. 2025.

Kids Definition

iron oxide

noun
: any of the oxides of iron
especially : ferric oxide

Medical Definition

iron oxide

noun
: any of several oxides of iron
especially : ferric oxide

More from Merriam-Webster on iron oxide

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