\ ˈtwin How to pronounce twin (audio) \

Definition of twin

 (Entry 1 of 3)

1a : either of two offspring produced in the same pregnancy
b Twins plural : gemini
2 : one of two persons or things closely related to or resembling each other
3 : a compound crystal composed of two adjoining crystals or parts of crystals of the same kind that share a common plane of atoms



Definition of twin (Entry 2 of 3)

1 : born with one other or as a pair at one birth my twin brother twin girls
2a : made up of two similar, related, or connected members or parts : double
b : paired in a close or necessary relationship : matching
c : having or consisting of two identical units
d : being one of a pair


twinned; twinning

Definition of twin (Entry 3 of 3)

transitive verb

1 : to bring together in close association : couple

intransitive verb

1 : to bring forth twins
2 of a crystal : to grow in a compound form with two adjoining sections that share a common plane of atoms

Other Words from twin


twinship \ ˈtwin-​ˌship How to pronounce twin (audio) \ noun

Synonyms & Antonyms for twin

Synonyms: Noun

Synonyms: Adjective

Antonyms: Adjective

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Examples of twin in a Sentence

Noun She's the mother of twins. The twins went swimming after lunch. My sister just had twins. Sarah and her brother are twins. Adjective the twin goals of reducing oil dependence and protecting the environment
Recent Examples on the Web: Noun For those who don't know or never had a reason to learn, the Bentayga Speed is powered by a 626-hp twin-turbocharged W-12 engine. Eric Stafford, Car and Driver, 20 Mar. 2022 Its southbound twin will open in a few more weeks after the paint striping, landscaping and other finishing touches are complete. Phil Diehl, San Diego Union-Tribune, 16 Feb. 2022 Initially, the admission had little impact on Dugar’s case, with a judge ruling in 2018 that Smith’s confession was not credible and declining to offer his twin a new trial, according to The Chicago Tribune. NBC News, 28 Jan. 2022 Baskets, created by Louis C.K., Zach Galifianakis and Jonathan Krisel, starred Galifianakis as Chip and Dale Baskets, one a struggling circus clown, the other his obnoxious identical twin. Chris Koseluk, The Hollywood Reporter, 21 Jan. 2022 The reactor and its twin, Point Beach 1, have been cited for safety violations and equipment malfunctions more than 130 times. Andrew Cockburn, Harper’s Magazine , 4 Jan. 2022 My two girls are out on their own (one of whom is his twin). Amy Dickinson,, 29 Nov. 2021 But unlike his twin, Don, Ron preferred to keep to himself. Jennifer Gonnerman, The New Yorker, 25 Oct. 2021 But episode 4 puts that theory to rest when Allison's dead body — which is actually the body of her twin, Lennon — washes up next to her sister in the ocean. Samantha Highfill,, 16 Oct. 2021 Recent Examples on the Web: Adjective My six-year-old twin grandchildren have never been told that their momma’s eggs came from an egg donor. Amy Dickinson, Washington Post, 17 May 2022 The twin-turbo V6 proved to be very responsive, especially when I was stuck behind someone pulling a pontoon boat to one of the local lakes now that the weather has warmed up. Sam Abuelsamid, Forbes, 16 May 2022 Top speed comes in at 181 with 542 horsepower of V8 4.0-liter twin-turbo engine power. Marc Grasso, Hartford Courant, 13 May 2022 Mechanical changes are limited, with the biggest being that Bentley is only going to offer the 542-hp twin-turbo 4.0-liter V-8 engine from the base Bentayga rather than the brawnier W-12 of the range-topper. Mike Duff, Car and Driver, 10 May 2022 The third-generation Toyota Sequoia will be available this summer with a twin-turbo V6 hybrid powertrain and a sliding third row with an adjustable cargo shelf system. Bymorgan Korn, ABC News, 8 May 2022 Raptor long ago abandoned its V-8 for a twin-turbo V-6. Tribune News Service, cleveland, 23 Apr. 2022 Despite air temperatures that hovered around 40 degrees in Indianapolis on Monday afternoon, Honda and Chevy managed to turn the first laps of the 2.4-liter twin-turbo V6 IndyCar engine era at the Indianapolis Motor Speedway. Nathan Brown, The Indianapolis Star, 29 Mar. 2022 The Maybach Exelero, thanks to the twin-turbo V12 engine, produced a top speed of 218 MPH. Yoni Heisler, BGR, 18 Feb. 2022 Recent Examples on the Web: Verb Kim Kardashian took a break from Skims bodysuits this Easter to twin with her kids. Glamour, 25 Apr. 2022 Now researchers are shooting for the loftiest goal: to twin the brain. Grace Browne, Wired, 15 Feb. 2022 For instance, healthcare professionals can one day digitally twin a patient’s body to test the impact of a treatment. Sayantan Dasgupta, Forbes, 7 Dec. 2021 The always stylish couple loves to keep their outfits coordinated and during a fashion fitting over the weekend, Union, 48, and Wade, 39, decided to twin in identical patterned pants. Kaitlyn Frey,, 25 Oct. 2021 If '1917' doesn't twin the top Oscar, 'Once Upon a Time … in Hollywood' will. Michael Phillips,, 25 Nov. 2020 Freeman led the Warriors to twin 5-5 seasons starting in 2015 until the breakthrough in 2017. Dennis Victory, al, 22 Oct. 2020 Their outing wouldn’t be the first time Witherspoon and her daughter were twinning. Robyn Merrett,, 23 Dec. 2019 Kylie and Stormi were just adorably twinning on vacay together. Katherine J Igoe, Marie Claire, 13 Dec. 2019 See More

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

First Known Use of twin


14th century, in the meaning defined at sense 1a


1593, in the meaning defined at sense 1


14th century, in the meaning defined at transitive sense 1

History and Etymology for twin


Middle English, from twin twofold


Middle English, twofold, double, from Old English twinn; akin to Old Norse tvinnr two by two, Old English twā two

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The first known use of twin was in the 14th century

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Last Updated

18 May 2022

Cite this Entry

“Twin.” Dictionary, Merriam-Webster, Accessed 25 May. 2022.

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More Definitions for twin


\ ˈtwin How to pronounce twin (audio) \

Kids Definition of twin

 (Entry 1 of 2)

1 : either of two offspring produced at one birth
2 : one of two persons or things closely related to or very like each other



Kids Definition of twin (Entry 2 of 2)

1 : born with one other or as a pair at one birth my twin brother
2 : made up of two similar, related, or connected members or parts a twin-engine airplane
3 : being one of a pair Her face was a pasty white with twin spots of rouge on the cheeks.— Gail Carson Levine, Ella Enchanted


\ ˈtwin How to pronounce twin (audio) \

Medical Definition of twin

 (Entry 1 of 2)

: born with one other or as a pair at one birth a twin brother twin girls



Medical Definition of twin (Entry 2 of 2)

1 : either of two offspring produced at a birth
2 twins plural : a group of two offspring born at one birth

Other Words from twin

twinship \ -​ˌship How to pronounce twin (audio) \ noun

More from Merriam-Webster on twin

Nglish: Translation of twin for Spanish Speakers

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


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