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
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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 Ochre, composed of iron oxide, clay, and silica, is more than just cave-art paint. New Atlas, 10 May 2025 This naturally occurring pigment is composed of iron oxide, clay, and silica and has been used by several species of hominins for thousands of years. Laura Baisas, Popular Science, 16 Apr. 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 21 Jul. 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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