\ 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

Since giving birth to twins in 2014, my pelvic floor—the sling of muscles running from the back to the front of the body—has been shot to pieces. The Economist, "For women, running is still an act of defiance," 28 June 2019 When the true bully emerged—one of a pair of twins whose mother, Celeste (Nicole Kidman), received regular brutal beatings at home from her husband Perry and so began to mimic his father’s violent behaviors—Renata had to recant. Rachel Syme, The New Republic, "Big Little Lies Gets Tough," 28 June 2019 Gemini is the sign of twins and is associated with two-faced-ness. Casey Newton, The Verge, "Project Veritas’ YouTube sting was deeply misleading — and successful," 27 June 2019 To their delight, Gabi gave birth to twins: a boy, a girl. Nathan Heller, The New Yorker, "The Perverse Logic of GoFundMe Health Care," 24 June 2019 Lia Farley gave birth to twins prematurely and, after complications, the infants died. Phoebe Wall Howard, Detroit Free Press, "A man who can build a car by hand leads Ford into future; 'He’s just never afraid'," 19 June 2019 The View co-host, 33, gave birth to twins — daughter Ruby Kate and son William Jeffrey — late on Wednesday, June 5, in New York City, PEOPLE confirms exclusively. Emily Strohm,, "It's a Girl — and a Boy! The View's Abby Huntsman Welcomes Twins Ruby Kate and William Jeffrey," 6 June 2019 The couple has three sons and two daughters, including two sets of twins among them. Michael Gold, New York Times, "Jennifer Dulos: Blood Found in Trash Matches That of Missing Connecticut Mother of 5," 3 June 2019 There's a reason why the Gemini symbol is a pair of twinsGet it now? Jasmine Gomez, Seventeen, "17 Gemini Memes That Totally Describe All Your Gemini Friends," 3 June 2019

Recent Examples on the Web: Adjective

Solving the twin problems of climate change and overuse will not be easy. John Fleck, The Conversation, "Western states buy time with a 7-year Colorado River drought plan, but face a hotter, drier future," 10 July 2019 But after being put into wartime service, the fates of the twin steamships Delta King and Delta Queen diverged wildly. Bill Van Niekerken,, "How twin SF-to-Sacramento steamships’ histories diverged in fantastic fashion," 10 July 2019 His twin location of Mabel’s BBQ are instant classics (and now the best BBQ in Las Vegas). Larry Olmstead, USA TODAY, "Great American Bites BBQ road trip: The country's best regional barbecue joints," 9 July 2019 Nanda Devi East is a twin peak of Nanda Devi, India's second-highest mountain, and the two are connected by a razor-sharp 1.2-mile ridge at an elevation of 22,000 feet. Fox News, "Final footage of climbers who died on Himalayan mountain in India revealed," 9 July 2019 That could be a heavy lift, given Colorado voters’ rejection of twin transportation funding initiatives last November. John Aguilar, The Denver Post, "RTD drills deep on funding for a Denver-to-Longmont train, aims to cut years off a 2050 debut," 9 July 2019 The twin temblors cracked the very foundations of the town. Gustavo Arellano,, "Massive earthquakes cracked the very foundations of the tiny but tough town of Trona," 8 July 2019 On June 27, twin suicide bombings in the capital, Tunis, targeted Tunisia's security forces and killed at least one person and injured several others. Michelle Lou, CNN, "Tunisia bans full-face coverings in public institutions after twin bombings," 5 July 2019 The streets of Omdurman, capital Khartoum's twin city across the Nile River, erupted in celebration when the news broke, a Reuters witness said. NBC News, "Sudan's rival groups reach power-sharing agreement after mass protests," 5 July 2019

Recent Examples on the Web: Verb

At the formal state dinner, Melania was also twinning with the Queen and Kate Middleton in white. Katherine J. Igoe, Marie Claire, "Melania Trump Channels Meghan Markle in Her Latest Hair Accessory," 7 June 2019 More: Flat Michigan revenue means no easy way for Whitmer to 'fix the damn roads' The Blue Water Bridge is actually two bridges, since the original span, opened to traffic in 1938, was twinned with a second bridge that opened to traffic in 1997. Paul Egan, Detroit Free Press, "GOP wants to explore selling Blue Water Bridge, other assets to fix Michigan roads," 5 June 2019 After coordinating outfits and even their hair, the couple has apparently moved on to twinning ink. Lauren Rearick, Teen Vogue, "Justin Bieber and Hailey Baldwin Reportedly Got Matching Tattoos," 2 Jan. 2019 Visit inside a tipi, watch 17th-century basketry twined, and observe finger-weaving. Annika Hom,, "Enjoy traditional dances at pow-wow in Danvers," 11 June 2019 Lanier, the father of virtual reality who moved on to work in AR and became an outspoken critic of social media, is a fitting spirit guide for the novel, twinning Stephenson's own slide into techno-pessimism. Peter Rubin, WIRED, "Neal Stephenson's Latest Book Dodges Its Scariest Premise," 4 June 2019 Kim and Kourtney twinned in vintage Versace for the iconic event, and the KKW Beauty founder showed off her incredible figure in a partially see-through minidress with a leg slit. Amy Mackelden, Harper's BAZAAR, "Kim Kardashian Does Superhero Chic in Red Latex at Travis Scott's 28th Birthday Party," 26 Apr. 2019 This is far from the first time that Meghan and Kate have twinned. Amy Mackelden, Harper's BAZAAR, "Kate Middleton Just Channeled Meghan Markle's Nautical Pants," 7 May 2019 Model Kate Vitamin found another kind of company, twinning with her cat in matching bleach blonde bobs, and game faces on. Akili King, Vogue, "Best Beauty Instagrams of the Week: Laura Harrier, Tracee Ellis Ross, and More," 10 Feb. 2019

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

13 Jul 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).


to form ideas or theories about something

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