\ 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

Either Ari is Hannah Montana-ing us all and living a double life as an influencer, or these two ladies are twins. Kelsey Stiegman, Seventeen, "This Fashion Blogger Looks JUST Like Ariana Grande and People Are Losing It," 21 Feb. 2019 But the report appeared to confirm that the twins and the third baby are real, and that the Chinese government believes CRISPRing babies is a bad idea. Julia Belluz, Vox, "Is the CRISPR baby controversy the start of a terrifying new chapter in gene editing?," 22 Jan. 2019 Singletons account for about 55 percent of all IVF births; 42 percent are twins, and 3 percent are triplets, according to George Annas, the Director of the Center for Health Law, Ethics & Human Rights at Boston University School of Public Health. Pamela Tsigdinos, Marie Claire, "The Wild World of IVF, Explained," 1 Oct. 2018 The bodies of Mara Lee Harvey, 41, Charlotte, 3, Alice and Beatrix, 2-year-old twins and Beverley Quinn, 73, were discovered by police in Perth on Sunday. Fox News, "Man kills wife, 3 young girls, grandmother in brutal stabbing: cops," 10 Sep. 2018 Through the now-defunct Louise Wise adoption agency, an unknown number of twins and triplets were placed in different homes and secretly observed for years by researchers who diligently made home visits. Amy Kaufman,, "The surreal, sad story behind the acclaimed new doc 'Three Identical Strangers'," 1 July 2018 Bunks, twins and trundles allow for more floor space. Marni Jameson,, "Designing a dreamy guest room for kids," 29 June 2018 One family photo shows all the siblings standing for a portrait, the twins and their older brother wearing what look like identical overalls. Ian Shapira, Washington Post, "Twin brothers died side by side in World War II. Now, they’re finally buried side by side.," 20 June 2018 The couple did an about-face and are now renting a 200-acre property in Oregon with plenty of room for their Living Vehicle, pets and daughter Eily, 8, and twins Wyatt and Nathaniel, 10. Lisa Boone, ajc, "People ditching pricey homes for small houses on wheels … and loving it," 29 May 2018

Recent Examples on the Web: Adjective

Tia Mowry and her twin sister Tamera are best known for their time on Sister, Sister, which ended its run in 1999. Emma Dibdin, Country Living, "Tia Mowry's Relationship With Husband Cory Hardrict Is Like a Real-Life Fairytale," 16 Dec. 2018 The first post, in slideshow format, begins with a joyful pic of her, Bush Sr., and Jenna's twin sister, Barbara (who's named after Bush Sr.'s wife, First Lady Barbara Bush). Tess Kornfeld, Glamour, "Jenna Bush Hager Remembers Her Grandfather, Former President George H. W. Bush, in a Touching Tribute," 1 Dec. 2018 The 41st president's granddaughter—who lived in the White House when her own father served as the 43rd President of the United States—first shared two photos of herself, her twin sister Barbara Bush, and their grandfather together. Chloe Foussianes, Town & Country, "Jenna Bush Hager Writes Powerfully of George H. W. Bush's Dream of Being Reunited With Loved Ones in the Afterlife," 1 Dec. 2018 During her wedding weekend, the bride also wore a floral, prairie-like white dress with sheer sleeves, according to a photo her twin sister Jenna Bush Hager posted on Instagram. Erica Gonzales, Harper's BAZAAR, "Barbara Bush Wore a Simply Stunning Wedding Dress by Vera Wang," 8 Oct. 2018 For those of you unfamiliar with the '80s cartoon reference, She-Ra is the twin sister of He-Man, and a sword-wielding royal rebel known for her strength. Lucy Wood, Marie Claire, "Meghan Markle's Favorite Princess as a Child Definitely Isn't Who You'd Expect," 14 Aug. 2018 That's two king pillows for a California king or king mattress, two standard pillows for a queen, and one standard pillow for a full or twin. Blake Bakkila, Good Housekeeping, "The Most Insane Presidents' Day Mattress Sales for Casper, Serta and More," 16 Feb. 2019 Antonio Pastini was killed when the twin-engine plane broke up shortly after takeoff and fell in pieces in Yorba Linda, igniting a fire in a home where four people died on Sunday. John Antczak, The Seattle Times, "Police: Pilot in fatal California crash had fake records," 6 Feb. 2019 Technology and science, the twin engines that propel the skincare industry, are both moving faster than ever. Evelyn Crowley, Vogue, "The 6 Biggest Skincare Breakthroughs of 2018," 19 Dec. 2018

Recent Examples on the Web: Verb

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 For the expecting royals Kate Middleton and Meghan Markle this year, twinning below-the-knee coats and dresses hinted at baby bump dressing with regal flair. Edward Barsamian, Vogue, "These Celebs Nailed the Art of Airport Style This Year," 28 Nov. 2018 In fact, Jordyn shared a photo to her Instagram Stories of the pair twinning from head to toe in grey sneakers, black workout clothes, and bleach-blonde hair. Zoë Weiner, Teen Vogue, "Jordyn Woods Dyed Her Hair a Bright Blonde," 27 Aug. 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

9 Mar 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

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