\ ˈī(-ə)rn How to pronounce iron (audio) \

Definition of iron

 (Entry 1 of 3)

1 : a silver-white malleable ductile magnetic heavy metallic element that readily rusts in moist air, occurs in pure form in meteorites and combined in most igneous rocks, is the most abundant element on Earth by mass, and is vital to biological processes — see Chemical Elements Table
2 : something made of iron: such as
a : a household device usually with a flat metal base that is heated to smooth, finish, or press (such as cloth)
b : any of a series of numbered golf clubs having relatively thin metal heads — compare wood
c irons plural : shackles for the hands or legs
d : a heated metal implement used for branding or cauterizing
e : stirrup usually used in plural
3 : great strength, hardness, or determination
iron in the fire
1 : a matter requiring close attention
2 : a prospective course of action

Definition of iron (Entry 2 of 3)

1 : of, relating to, or made of iron
2 : resembling iron
3a : strong and healthy : robust an iron constitution
b : inflexible, unrelenting iron determination
c : holding or binding fast an iron grip


ironed; ironing; irons

Definition of iron (Entry 3 of 3)

transitive verb

1a : to smooth with or as if with a heated iron iron a shirt
b : to remove (something, such as wrinkles) by ironing
2 : to shackle with irons
3 : to furnish or cover with iron

intransitive verb

: to smooth or press cloth or clothing with a heated iron

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Other Words from iron


ironness \ ˈī(-​ə)rn-​nəs How to pronounce ironness (audio) \ noun

Synonyms & Antonyms for iron

Synonyms: Noun

Synonyms: Adjective

Antonyms: Adjective

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Examples of iron in a Sentence

Adjective he had an iron determination to succeed in on Wall Street
Recent Examples on the Web: Noun Divided into local unions, there were the men who build our cities—the carpenters, steel and iron workers, masons, painters and decorators. San Diego Union-Tribune, "From the Archives: Celebrating a solemn Labor Day," 6 Sep. 2020 Okra gel is rich in Vitamins A, C, and B, as well as protein, magnesium, iron, calcium, and folate. Christal Lewis, Glamour, "The Wash-Day Products Chrissy Got the Coils Swears By for Type 4 Hair," 3 Sep. 2020 Then there are the alkaline wastes from aluminum, iron, steel, and cement production, which could bring the total up to at least 310 million tons—and by some estimates more than 4 gigatons (GTs)—of CO2 trapped each year. Robert F. Service, Science | AAAS, "Industrial waste can turn planet-warming carbon dioxide into stone," 3 Sep. 2020 At the prison, men, women and children were shackled to iron beds and tortured before they were beaten to death, prosecutors said. Helen Regan, CNN, "Khmer Rouge executioner 'Comrade Duch' who oversaw notorious torture prison dies age 77," 2 Sep. 2020 Researchers at Northwestern University have developed a reusable sponge coated in a mixture containing iron and carbon that can absorb 30 times its weight in oil. Sarah Mcfarlane, WSJ, "Future of Cleaning Oil Spills Looks to Robots, Wood Chips and Sponges," 29 Aug. 2020 Most varieties of corn are good sources of dietary fiber, the B vitamins thiamin and folate, and a handful of minerals, including potassium, iron and magnesium. Darlene Zimmerman, Detroit Free Press, "Have a garden load of zucchini? Pair with summer corn for fresh tasting relish," 28 Aug. 2020 My first shipment contained two pouches of a starter fertilizer containing seaweed extracts and iron. Andrea Beck, Better Homes & Gardens, "This New Subscription Service Provides an Easy Solution to Fertilizing Your Lawn," 28 Aug. 2020 Using iron, pycnonuclear science, and a computer, one scientist has scheduled the end of the universe. Caroline Delbert, Popular Mechanics, "Sad! This Is When the Universe Will Truly End," 24 Aug. 2020 Recent Examples on the Web: Adjective Check out this Nordstrom trim-fit non-iron dress shirt, which drops from $39.50 to $19.75 in the Red Ruby hue. Arielle Tschinkel, USA TODAY, "Nordstrom is having a huge sale on some of its top-rated brands ahead of the Anniversary Sale," 29 July 2020 Check out this Nordstrom traditional fit non-iron dress shirt, which drops a full 70% in select colors and sizing from $49.50 to $14.85. Nicole Briese, USA TODAY, "Nordstrom is having a huge sale-on-sale and the deals are incredible," 10 July 2020 In ancient seas, iron aplenty To learn how iron fertilization might work in the future, some researchers are looking at the past, in paleoclimate records such as ice cores and deep-sea sediments. Emily Underwood, Smithsonian Magazine, "The Complicated Role of Iron in Ocean Health and Climate Change," 6 Jan. 2020 Recent Examples on the Web: Verb My uniform—a blazer and slacks of ocean-blue polyester, with a patch depicting a sun rising over the pages of an open book sewn halfway up the right sleeve—was freshly ironed. Alex Halberstadt, The New Yorker, "October’s Child: The Year I Left the Soviet Union," 5 Apr. 2020 Talley was raised by a great-grandmother and grandmother who boiled the laundry and ironed the sheets. Rumaan Alam, The New Republic, "André Leon Talley Corrects the Record," 19 May 2020 The president normally has two office valets and three in the residence to act as personal assistants, doing everything from serving meals to ironing his clothes. Eli Stokols, Los Angeles Times, "Second White House aide tests positive for coronavirus," 8 May 2020 All fabrics received are left outside for 48 hours before being washed, dried, and ironed for safety. Jenna Schoenefeld, Popular Mechanics, "How Citizens Are Helping Healthcare Workers Fight the Coronavirus," 6 May 2020 Pin It, Steam It, Stitch It The corners were darted to make the curved corners smooth while quilting pins were used to keep everything in place while folding the unfinished edges beneath and ironing to get the material to lay flat and smooth. Eric Hockman, Sunset Magazine, "Sewing for Beginners: How I Made Waxed Canvas Window Covers For My Camper," 30 Apr. 2020 The inner layer is made of thin cotton and has a stabilizer ironed on. John Delapp, Houston Chronicle, "Quilting group’s face masks go to firefighters, hospitals," 13 Apr. 2020 The preliminary settlement resolves claims that the company used a timekeeping system that cheated workers out of overtime, barred them from taking rest breaks during their shifts, and forced them to clean and iron their uniforms out of pocket. Washington Post, "McDonald’s to pay $26 million to settle worker underpayment claims in California," 25 Nov. 2019 The white cloth, once freshly ironed, bears the trace of a concertina of folds. The Economist, "The first “Last Supper” painted by a woman goes on public display," 23 Oct. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'iron.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of iron


before the 12th century, in the meaning defined at sense 1


before the 12th century, in the meaning defined at sense 1


15th century, in the meaning defined at transitive sense 3

History and Etymology for iron


Middle English, from Old English īsern, īren; akin to Old High German īsarn iron

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Time Traveler for iron

Time Traveler

The first known use of iron was before the 12th century

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Statistics for iron

Last Updated

11 Sep 2020

Cite this Entry

“Iron.” Dictionary, Merriam-Webster, Accessed 20 Sep. 2020.

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More Definitions for iron


How to pronounce iron (audio)

English Language Learners Definition of iron

 (Entry 1 of 3)

: a heavy type of metal that is very common, occurs naturally in blood, and is used to make steel and in many products
: a device with a flat metal base that is heated and is used to press wrinkles out of clothing
: a golf club that has a metal head and is identified by a number

English Language Learners Definition of iron (Entry 2 of 3)

: made of iron
: very strong



English Language Learners Definition of iron (Entry 3 of 3)

: to use a heated iron to make clothing or fabric smooth


\ ˈī-ərn How to pronounce iron (audio) \

Kids Definition of iron

 (Entry 1 of 3)

1 : a heavy silvery white metallic chemical element that rusts easily, is strongly attracted by magnets, occurs in meteorites and combined in minerals, and is necessary for transporting oxygen in the blood
2 : a device that is heated and used for making cloth smooth
3 : a device that is heated to perform a task a soldering iron
4 irons plural : handcuffs or chains used to bind or to hinder movement

Kids Definition of iron (Entry 2 of 3)

1 : made of iron
2 : strong and healthy He has an iron constitution.
3 : not giving in an iron will


ironed; ironing

Kids Definition of iron (Entry 3 of 3)

: to press with a heated iron


\ ˈī(-ə)rn How to pronounce iron (audio) \

Medical Definition of iron

1 : a heavy malleable ductile magnetic silver-white metallic element that readily rusts in moist air, occurs native in meteorites and combined in most igneous rocks, is the most used of metals, and is vital to biological processes (as in transport of oxygen in the body) symbol Fe — see Chemical Elements Table
2 : iron chemically combined iron in the blood

Other Words from iron

iron adjective

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Comments on iron

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