iron oxide


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

Example Sentences

Recent Examples on the Web Ferrite magnets, made of iron oxide, are cheaper alternatives. Mary Hui, Quartz, 3 Mar. 2023 Cosmetic tattoos, such as lip liner and microbladed eyebrows, are difficult to remove with lasers due to the presence of iron oxide or titanium dioxide, Dr. Alster says. Tim Newcomb, Popular Mechanics, 27 Sep. 2022 To manufacture iron, hydrogen is used to transform one molecule of iron oxide (Fe2O3) into two molecules of iron (Fe) and three molecules of water (H2O) at high temperatures—fossil fuels are currently used for this purpose. Smithsonian Magazine, 22 Feb. 2023 Closer inspection with X-ray fluorescence and a scanning electron microscope showed that the dirt was full of iron oxide and microscopic fragments of hematite. Kiona N. Smith, Ars Technica, 3 Mar. 2022 More recently, she’s been part of a team that used the University of Rochester’s Omega Laser Facility to compress samples of iron oxide — one of the main constituents of our planet’s mantle — up to 7 million times Earth’s atmospheric pressure. Quanta Magazine, 15 June 2021 The ripply pinkish stuff between the dunes is made of smaller grains of sand laden with iron oxide -- rust! Phil Plait, Discover Magazine, 7 Dec. 2010 The moon has a much higher iron oxide (FeO) concentration than Earth. Korey Haynes, Discover Magazine, 29 Apr. 2019 Colonial homes were often accented with an earthy red color derived from the natural clay pigment red ochre (the reddish tint comes from iron oxide), making the hue an appropriate choice for the 1800s cabin. Shaila Wunderlich, Country Living, 3 Jan. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'iron oxide.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1790, in the meaning defined above

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

Dictionary Entries Near iron oxide

Cite this Entry

“Iron oxide.” Dictionary, Merriam-Webster, Accessed 30 Mar. 2023.

Kids Definition

iron oxide

: any of the oxides of iron
especially : ferric oxide

Medical Definition

iron oxide

: any of several oxides of iron
especially : ferric oxide

More from Merriam-Webster on iron oxide

Last Updated: - Updated example sentences
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