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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Meanwhile, iron oxides provide additional protection against visible light that can worsen hyperpigmentation. Jenny Berg, Glamour, 22 June 2026 The acid in vinegar reacts with iron oxide and dissolves the rust. Brandee Gruener, Southern Living, 22 June 2026 To address the problem, the researchers engineered a heterointerface combining iron oxide (Fe2O3) and samarium oxide (Sm2O3). Neetika Walter, Interesting Engineering, 13 June 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 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 27 Jun. 2026.

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

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