\ 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

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Other Words from twin


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

Synonyms & Antonyms for twin

Synonyms: Noun

companion, fellow, half, match, mate

Synonyms: Adjective

binary, bipartite, double, double-barreled, double-edged, dual, duplex, twofold

Antonyms: Adjective


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Examples of twin in a Sentence


She's the mother of twins. The twins went swimming after lunch. My sister just had twins. Sarah and her brother are twins.


the twin goals of reducing oil dependence and protecting the environment
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Recent Examples on the Web: Noun

Malin himself, the new dad to a pair of twins (check out their Cali-chic playroom!), worked with the upholstery brand to create a 45-piece collection that includes everything from pint-sized seating and headboards to storage ottomans and throws. Emma Bazilian, House Beautiful, "Instagram’s Hottest Photographer Just Launched a Kids’ Line Even Adults Will Love," 25 Apr. 2019 Two sets of twins, really, separated at birth and raised in completely different circumstances (two of them are country gals, the other are city gals, naturally) and who convene in New York City for a really weird weekend. Marie Claire, "The 17 Best Movies on HBO Go to Watch Right Now," 28 Feb. 2019 Nearby beaches and other prime viewing spots were packed with tourists and locals eager to catch not just the launch but the rare and dramatic return of twin boosters, accompanied by sonic booms. Marcia Dunn, The Seattle Times, "SpaceX launches mega rocket, lands all 3 boosters," 14 Apr. 2019 The eight people in the minivan — including 1-year-old twins and four other children under age 15 — were taken to hospitals with injuries, and the driver had to be extricated from the van by firefighters. Sarah Freishtat, Aurora Beacon-News, "Ambulance driver in crash that sent 10 to hospitals showed 'due regard,' Aurora fire marshal says," 22 June 2018 Stanley went house hunting with the Olsen twins in Bel Air, oversaw a full renovation of their home, and spent a year shopping with them for furniture. Vanessa Lawrence, ELLE Decor, "This Remodeled Los Angeles Home is a Magnet for Friends and Hollywood Stars Alike," 11 Mar. 2019 Its most popular model, the Leesa, ranges from $505 for a twin to $1,015 for a California King. Christian Allaire, Vogue, "7 New Online Mattress Companies That Want To Sweeten Your Dreams," 15 Feb. 2019 For this reason, most company's sizing for twin, queen, and king weighted blankets will be smaller dimensions than traditional blankets. Lexie Sachs, Good Housekeeping, "The 5 Best Weighted Blankets to Help You Get the Best Sleep of Your Life," 21 Nov. 2018 The findings are similar for twins who have Type 1 diabetes, which is known to have a strong genetic component. Denise Grady, The Seattle Times, "Anatomy does not determine gender, experts say," 22 Oct. 2018

Recent Examples on the Web: Adjective

Shop king mattresses at the price of a queen mattress and queen mattresses at the price of a twin mattress, resulting in up to $700 in savings. Shanon Maglente, Good Housekeeping, "Where to Find the Best Memorial Day Mattress Deals of 2019," 14 May 2019 Its twin fuselages — sort of the airplane equivalent of a catamaran — are 238 feet (72.5 meters) long. John Antczak, The Seattle Times, "Giant Stratolaunch aircraft lifts off from California," 13 Apr. 2019 Astronauts may be better able to withstand long missions to the Moon and even Mars than previously realized, lifting what had loomed as a barrier to space exploration, a unique study of twin astronauts revealed. Robert Lee Hotz, WSJ, "Astronauts Can Withstand Longer Space Trips, New Study of Twins Finds," 11 Apr. 2019 Casiraghi's cousins, Prince Albert's twin four-year-olds, Prince Jacques and Princess Gabriella, will also be in the wedding party. Chloe Foussianes, Town & Country, "Charlotte Casiraghi's Wedding to Dimitri Rassam Is Reportedly This Summer—Here's Everything We Know," 10 Apr. 2019 In the first successful human transplant, in 1954, Ronald Herrick, 23, donated a kidney to his identical twin brother Richard at the Peter Bent Brigham Hospital in Boston. Joshua Mezrich, WSJ, "Losing the Humanity of Transplants," 18 Jan. 2019 Not Nicole, who opens up to Colton about her twin brother having autism. Anna Moeslein, Glamour, "The Bachelor Season 23, Episode 2 Recap: Is Demi This Season's Villain?," 14 Jan. 2019 His twin brother, Joaquin Castro, is a Democratic congressman from Texas. Paul J. Weber, The Seattle Times, "APNewsBreak: Julian Castro moves toward 2020 White House run," 12 Dec. 2018 Auben is spirited and popular, but he’s been branded with six different vices on his arms, while his twin brother Kasim only has one — which can make all the difference for a successful future. Andrew Liptak, The Verge, "All the science fiction and fantasy books that you should check out this month," 1 Aug. 2018

Recent Examples on the Web: Verb

These twinning Instagram posts are a Jonas family engagement tradition. Kayleigh Roberts, Marie Claire, "Priyanka Chopra and Nick Jonas Officially Confirmed Their Engagement in Matching Instagrams," 18 Aug. 2018 Husband Prince Harry wore the same shirt, leading to the cutest twinning moment: From exhibiting swoon-worthy PDA on Bondi Beach, to receiving some carrots as a gift, Meghan and Harry's royal tour is off to an unforgettable start. Amy Mackelden, Harper's BAZAAR, "Meghan Markle Just Traveled to Cockatoo Island Wearing the Coolest Shades," 20 Oct. 2018 View this post on Instagram A post shared by Kendall (@kendalljenner) on Feb 4, 2019 at 5:35pm PST Whether or not Hadid shared a screenshot of Jenner's Instagram pic to her stylist to recreate these bangs, the two models are twinning hard right now. Maya Allen, Marie Claire, "Bella Hadid Debuts Clip-In Bangs One Day After Kendall Jenner Posted a Selfie of Hers," 7 Feb. 2019 The beauty is, quite literally, twinning with herself. Avery Matera, Teen Vogue, "Selena Gomez Copied Her Own Outfit From "Barney" in 2003," 21 Aug. 2018 Everly is twinning with her fairy hero in a green princess dress (with matching wings, naturally) and even a half topknot. Katherine J. Igoe, Marie Claire, "Everly Tatum Fangirls over Her 'Idol' at Disneyland—and Jenna Dewan Films the Sweet Moment," 18 Feb. 2019 The generous aunt surprised the baby girl with a mini neon-green Mercedes-Benz G-Class from Mercedes Beverly Hills to twin with her mother, Kim Kardashian. Nicole Saunders, Harper's BAZAAR, "Kim Kardashian's Daughter, Chicago West, Gets a Mini Mercedes G-Wagon to Match with Mom," 16 Jan. 2019 Kylie Jenner has unexpectedly twinned with Meghan Markle, by wearing one of the iconic dresses the duchess wore during the royal tour in October 2018. Amy Mackelden, Harper's BAZAAR, "Kylie Jenner and Meghan Markle Are Unexpected Style Twins in the Same Maggie Marilyn Tuxedo Dress," 1 Jan. 2019 Chloe x Halle twinned in sheer white looks for their performance on Fallon Tonight. Liana Satenstein, Vogue, "The Best Fashion Instagrams of the Week: Florence Welch Goes Full Rockstar, Zendaya Is Ready to Party, and More," 15 Dec. 2018

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.

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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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Dictionary Entries near twin






twin band mill

twin bed

Statistics for twin

Last Updated

18 May 2019

Look-up Popularity

Time Traveler for twin

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

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More Definitions for twin



English Language Learners Definition of twin

 (Entry 1 of 3)

: either one of two babies that are born at the same time to the same mother
: either one of two similar things that form a pair



English Language Learners Definition of twin (Entry 2 of 3)

used to describe children who are twins
: made up of two similar things that are used together
: forming one of a pair of related or connected ideas or places



English Language Learners Definition of twin (Entry 3 of 3)

: to bring (two things) together in close association
British : to form a relationship between (two towns in two countries)


\ 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 On the opposite side of the river is the city's twin.



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 twinship (audio) \ noun

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More from Merriam-Webster on twin

Rhyming Dictionary: Words that rhyme with twin

Thesaurus: All synonyms and antonyms for twin

Spanish Central: Translation of twin

Nglish: Translation of twin for Spanish Speakers

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

Comments on twin

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


highly pertinent or appropriate

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