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flatiron

American  
[flat-ahy-ern] / ˈflætˌaɪ ərn /
Or flat iron

noun

  1. an iron for pressing clothes or fabric, especially an old-fashioned, nonelectric one that is typically made of cast iron and heated on a woodstove.

    I kept an old, heavy flatiron from my great-grandmother’s house as a memento.

  2. Usually flat iron an electric device for straightening or styling hair by pulling it between two flat, heated surfaces.

    It takes me forever to straighten my hair with a flat iron.

  3. Usually flat iron steak a cut of beef taken from the chuck, or front shoulder.

    This grilled flat iron steak is marinated in a garlic and herb sauce.

    The prix fixe menu combines three cuts—hanger, ribeye, and flat iron—with a variety of Korean accompaniments.

  4. a building that is triangular in shape (usually used attributively).

    The flatiron building downtown was built in 1892.

  5. Geology. (especially in the Western United States) a long, triangular, crested ridge that resembles an iron resting on its base.


verb (used with object)

  1. Usually flat iron to style (hair) with a flat iron.

    I went from blow-drying and flat ironing my hair every day to just drying it naturally.

flatiron British  
/ ˈflætˌaɪən /

noun

  1. (formerly) an iron for pressing clothes that was heated by being placed on a stove, etc

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of flatiron

First recorded in 1735–45; flat 1 + iron

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Cosby Flatiron Books: Pine & Cedar: 352 pages, $29 If you buy books linked on our site, The Times may earn a commission from Bookshop.org, whose fees support independent bookstores.

From Los Angeles Times • Apr. 16, 2026

According to models developed at the Flatiron Institute, that motion prevents most of the outer material from plunging straight into the black hole.

From Science Daily • Feb. 14, 2026

"That's where the mystery really started," said De, a professor at New York's Columbia University and researcher at the Flatiron Institute.

From Barron's • Feb. 12, 2026

Valerie Pimpinelli, wine buyer and general manager of Flatiron Wines & Spirits in New York, said that although she loves Champagnes made by small growers, “for a lot of people Veuve is the only option.”

From The Wall Street Journal • Dec. 11, 2025

“Something like that. Google says the architect of the Flatiron Building ‘hanged himself after it was completed, because he forgot to put in a men’s restroom and was humiliated.’”

From "Better Nate Than Ever" by Tim Federle

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