\ 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

One is shunning nonstick cookware in favor of cast iron or stainless steel, Trasande said. Ellen Knickmeyer,, "Hard to avoid PFAS: Nonstick, stain-resistant compounds are ‘everywhere’," 22 July 2019 One is shunning nonstick cookware in favor of cast iron or stainless steel, Trasande said. Washington Post, "What consumers can do as regulators weigh compounds’ risks," 20 July 2019 However, cast iron does have a reputation for being difficult to clean. Joseph Truini, Popular Mechanics, "How To Clean a Cast-Iron Pan," 3 June 2019 This dish can absolutely be done on the grill for your outdoor cooking pleasure, but the evenly flat surface of the short ribs lends itself to searing in a hot skillet (preferably cast iron), which gives you a deeply browned crust. Alison Roman, New York Times, "Short Ribs for Summer, Doused With Salsa," 15 July 2019 Try a pizza stone on the oven floor; start in a cast iron skillet on the stovetop and finish under the broiler; or slide the dough onto a hot grill. Leigh Belanger,, "Recipe: It couldn’t be easier (or better) to grill pizza dough, then add zucchini slices and ricotta," 14 July 2019 One of the new menu items is a baked lasagna made in a cast iron with ricotta, parmesan and lemon. Samantha Incorvaia, azcentral, "Renovated Tempe Public Market Cafe reopening without co-owner and chef Aaron Chamberlin," 6 June 2019 Both are, however, vulnerable to chips or breaks if subjected to blunt force in unsupported areas—like, say, by dropping a cast iron skillet right on the corner of your counter—and both can stain. Hannah Morrill, ELLE Decor, "The Main Differences Between Quartz and Granite," 17 June 2019 For comparison, consider that cast iron melts at about 2,200 degrees Fahrenheit. Glenn Mcdonald, National Geographic, "From diamonds to rockets, mourning the dead has gotten high-tech," 17 June 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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Time Traveler for cast-iron

The first known use of cast-iron was in 1664

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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).


a period when something is suspended

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