iron oxide

noun

: any of several oxides of iron: such as
a
: ferric oxide
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.
Titanium dioxide and iron oxides supply the pigment—though the former doesn’t make this a substitute for sunscreen—and light-reflecting mica keeps the finish from looking flat. — Christa Joanna Lee, Allure, 6 Sep. 2026 The results suggest the bright red pigment came from a clay rich in tiny particles of iron oxide, or haematite. — Mike McRae 17, New Atlas, 17 Aug. 2026 Rather than relying on traditional petrochemical dyes, the company uses biopolymers and iron oxide to create what Berlan describes as a hybrid molecule. — Christopher McFadden, Interesting Engineering, 7 Aug. 2026 For anyone worried about dark spots, iron oxides are the ingredient to watch. — Lauren Jarvis-Gibson july 1, Charlotte Observer, 1 July 2026 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

Rhymes for iron oxide

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Browse Nearby Words

iron out the wrinkles
iron oxide
iron-oxide red
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Cite this Entry

“Iron oxide.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/iron%20oxide. Accessed 7 Sep. 2026.

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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

Britannica.com: Encyclopedia article about iron oxide

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