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

Definition of cast-iron

 (Entry 1 of 2)

1 : made of cast iron
2 : resembling cast iron: such as
a : capable of withstanding great strain a cast-iron stomach
b : not admitting change, adaptation, or exception : rigid a cast-iron will
c British : not likely to fail or be broken : airtight "Clever idea, Black, getting yourself seen on a safe station platform … gave you a cast-iron excuse not to leave your hidey-hole in future, didn't it?"— J. K. Rowling

cast iron


Definition of cast iron (Entry 2 of 2)

: a commercial alloy of iron, carbon, and silicon that is cast in a mold and is hard, brittle, nonmalleable, and incapable of being hammer-welded but more easily fusible than steel

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Synonyms & Antonyms for cast-iron

Synonyms: Adjective

brassbound, exacting, hard-line, inflexible, rigid, rigorous, strict, stringent, uncompromising

Antonyms: Adjective

flexible, lax, loose, relaxed, slack

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Examples of cast-iron in a Sentence


The fence is made of cast iron.

Recent Examples on the Web: Noun

To accommodate a large group of guests, the party version of Jollof is also cooked in cast iron pots over firewood, giving it a smokey flavor served at parties with fried plantains and moin moin (steamed bean pudding). Haleluya Hadero, Quartz Africa, "How Jollof rice became West Africa’s iconic dish and a point of banter between Africans," 23 Aug. 2019 Special touches: Outside, cast iron lawn furniture painted vibrant colors gives a nice hippie-at-the-beach vibe. Christina Tkacik,, "Imaginative food and a uniquely Baltimore experience at Gypsy’s Truckstaurant," 1 Aug. 2019 Shop the brand's best deals happening right now below: If the Lodge cookware is beyond your budget, AmazonBasics also slashed the price on its enameled cast iron covered Dutch ovens, from $40 to to $28. Caroline Picard, Good Housekeeping, "Lodge Cast-Iron Cookware Is More Than 50% Off for Amazon Prime Day," 15 July 2019 Other European products identified Monday for potential tariffs included Edam and Gouda cheese, roasted coffee, olives, and cast iron pipes. Amie Tsang,, "US proposes new tariffs on $4 billion of EU goods as trade dispute grows," 2 July 2019 Also, look for grills with innards are also made with stainless steel — especially the grates and burners — instead of cheaper, less durable materials like cast iron or sheet steel. Richard A. Marini, San Antonio Express-News, "S.A.’s money’s no object, high-end outdoor kitchens," 2 July 2018 Nothing beats cast iron for browning, frying and baking. Eric Velasco,, "The best kitchen tools and how to use them," 27 Apr. 2018 Made to inspire oohs and ahhs, the dish is the spiritual cousin of the Tex-Mex fajita served on a hot cast iron skillet. Soleil Ho,, "In fine dining, soup is the ultimate humblebrag," 2 Sep. 2019 In a 9-inch cast iron or ovenproof skillet over medium heat, melt the butter. Sally Pasley Vargas,, "Recipes: Three refreshing blueberry desserts," 24 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cast-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 cast-iron


1692, in the meaning defined at sense 1


1664, in the meaning defined above

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Statistics for cast-iron

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Time Traveler for cast-iron

The first known use of cast-iron was in 1664

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More Definitions for cast-iron



English Language Learners Definition of cast-iron

 (Entry 1 of 2)

: made of cast iron
: very strong or tough
British : not likely to fail or be broken

cast iron


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

: a very hard type of metal that is made into different shapes by being melted and poured into special containers (called casts or molds)

cast iron


Kids Definition of cast iron

: a hard and brittle alloy of iron, carbon, and silicon shaped by being poured into a mold while melted

More from Merriam-Webster on cast-iron

Rhyming Dictionary: Words that rhyme with cast-iron

Thesaurus: All synonyms and antonyms for cast-iron

Comments on cast-iron

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


to be made up of

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