\ 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 native in meteorites and combined in most igneous rocks, is the most used of metals, 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: Adjective

firm, forceful, hearty, lusty, robust, solid, stout, strong, sturdy, vigorous

Antonyms: Adjective

uncertain, weak

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Examples of iron in a Sentence


he had an iron determination to succeed in on Wall Street

Recent Examples on the Web: Noun

Today, the Top League -- Japan's semiprofessional rugby league that supplies most of its international players -- is comprised of corporate teams, specifically from iron, steel, auto-making, and manufacturing industries which employ the players. George Ramsay, CNN, "Japan set to host 'special' World Cup as rugby steps into the unknown," 17 Sep. 2019 Cut iron-on adhesive same size as stripes; iron it onto the stripes, then iron the stripes onto the front. Glue the front to the back where marked. Michele Filon, Woman's Day, "Candy Corn Treasure," 9 Sep. 2019 Late-Night Spa: Wi Spa View this post on Instagram With the help of thousand-year-old minerals such as calcium, magnesium, iron, sodium and selenium, our salt sauna improves the physical, chemical and hydrodynamic conditions of the body. Taylore Glynn, Marie Claire, "The Must-Visit Spas & Salons in Los Angeles," 6 Sep. 2019 Noise-fighting measures include a cast block of compacted graphite iron, offset piston pins to reduce piston slap and a two-piece oil sump that uses sandwiched polymer and metal material. Jeff Yip, Houston Chronicle, "2020 Ram EcoDiesel is strong, silent, but how fuel-stingy will it be?," 6 Sep. 2019 Since almost all meteorites have tiny bits of iron embedded in them, magnets are a fairly easy way to find them. Meg Jones, Milwaukee Journal Sentinel, "When a meteorite plunged into Lake Michigan, a team of scientists built a sled with magnets to find it," 4 Sep. 2019 Those metal coils can be composed of a variety of substances, including an alloy of iron, chromium and aluminum called kanthal, or a combination of nickel and chromium. NBC News, "What is in a vape? Everything you need to know," 3 Sep. 2019 His closest brush with art school was lessons from a blacksmith who taught him to weld and forge iron, skills that would be essential to his art and enable him to support himself by working for ironmongers. Roberta Smith, New York Times, "Takis, Sculptor Who Made Art From Moving Parts, Dies at 93," 30 Aug. 2019 Step 4: Use a household iron, on the cotton setting, to activate the glue, and press the veneer into position on the edges of the panels. Elizabeth Gulino, House Beautiful, "Your Step-by-Step Guide to Building a Platform Bed Frame," 30 Aug. 2019

Recent Examples on the Web: Verb

One focus since joining the system is ironing a swing that had been geared to load up to damage baseballs. San Diego Union-Tribune, "Minors: How Storm’s Gabriel Arias is tapping into his power," 16 Aug. 2019 In homes people wake up in the middle of the night to cook or iron their shirts. The Economist, "Zimbabwe’s economy is crashing and its people are hungry," 15 Aug. 2019 With any luck the LOUD Weekend will continue in future years, and the growing pains will iron themselves out. Zoë Madonna,, "Bang on a Can turns up the volume with LOUD Weekend at Mass MoCA," 3 Aug. 2019 Think about using the vintage ironing closet for some of your supplies. Bang Staff And Correspondents, The Mercury News, "Sponsored: Attractive vintage home on huge lot," 30 July 2019 The San Francisco 49ers and place kicker Robbie Gould agreed to a new deal early Monday morning, and with an hour before the 4 p.m. ET deadline, the Atlanta Falcons had ironed theirs out with defensive tackle Grady Jarrett. Lorenzo Reyes, USA TODAY, "Franchise-tag roundup: Robbie Gould, Grady Jarrett get new deals; Texans' Jadeveon Clowney doesn't," 15 July 2019 Their white shirts were ironed, their shoes were vigorously shined and their faces had been scrubbed clean. Maria Petrakis,, "Wanted: People willing to live on a beautiful, remote Greek island," 6 June 2019 Women who stepped in and made sure my hair was done right, clothes were ironed, spirit was high and unbroken. Harmonyholiday, Longreads, "Mama Looks for Melanin," 6 June 2019 Anyone can iron Jim Bob’s shirt, anybody can make lunch for him. Sophie Dodd,, "'Be Joyfully Available for Him ... Even Though You May Be Exhausted and Big Pregnant': The Duggar Family's Most Candid Sex Tips," 28 June 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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Dictionary Entries near iron





Iron Age

iron alum


Statistics for iron

Last Updated

20 Sep 2019

Look-up Popularity

Time Traveler for iron

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

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More Definitions for iron



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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More from Merriam-Webster on iron

Thesaurus: All synonyms and antonyms for iron

Spanish Central: Translation of iron

Nglish: Translation of iron for Spanish Speakers

Britannica English: Translation of iron for Arabic Speakers Encyclopedia article about iron

Comments on iron

What made you want to look up iron? Please tell us where you read or heard it (including the quote, if possible).


concealment of treason or felony

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