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.
The acid in vinegar reacts with iron oxide and dissolves the rust. — Brandee Gruener, Southern Living, 22 June 2026 For anyone worried about dark spots, iron oxides are the ingredient to watch. — Lauren Jarvis-Gibson july 1, Charlotte Observer, 1 July 2026 Others in the field, however, dismissed the markings as natural phenomena, such as iron oxide deposits, which also look red. — Adam Kovac, Scientific American, 1 June 2026 The sand here was created by the erosion of nearby Navajo sandstone, and the rock gets its reddish-orange color from the iron oxide mineral hematite. — Lydia Mansel, Travel + Leisure, 2 Apr. 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 8 Jul. 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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