twin
1 Americannoun
-
either of two children or animals brought forth at a birth.
-
either of two persons or things closely related to or closely resembling each other.
-
Also called twin room. a type of hotel accommodation with twin beds, for occupancy by two persons.
-
Also called hemitrope. Crystallography. a compound crystal consisting of two or more parts or crystals definitely oriented each to the other; macle.
-
Astronomy, Astrology. Twins, the constellation or sign of Gemini.
adjective
-
being a twin or twins.
twin sisters.
-
being two persons or things closely related to or closely resembling each other.
-
being one of a pair; identical.
a twin bracelet; a twin peak.
-
consisting of two similar parts or elements joined or connected.
a twin vase.
-
Botany, Zoology. occurring in pairs; didymous.
-
Crystallography. of the nature of a twin; hemitrope.
-
twofold or double.
verb (used with object)
-
to furnish a counterpart to or a replica of; match.
-
Informal. to divide or convert into two, parts, similar items, etc..
The old movie palace will be twinned, making two smaller theaters.
-
Informal. to link or combine with.
The new grocery store is twinned with a restaurant.
-
Crystallography. to form into a twin.
-
Obsolete. to give birth to as twins.
verb (used without object)
-
to give birth to twins.
-
to be paired or coupled.
-
to match or resemble someone or something in a specific way, and to acknowledge this resemblance: Check out these photos of moms and daughters twinning!
They are twinning so hard right now.
Check out these photos of moms and daughters twinning!
verb (used with or without object)
noun
-
-
-
either of two persons or things that are identical or very similar; counterpart
-
( as modifier )
twin carburettors
-
-
Also called: macle. a crystal consisting of two parts each of which has a definite orientation to the other
verb
-
to pair or be paired together; couple
-
(intr) to bear twins
-
(intr) (of a crystal) to form into a twin
-
archaic (intr) to be born as a twin
-
(tr)
-
to create a reciprocal relation between (two towns in different countries); pair (a town) with another in a different country
-
(intr) (of a town) to be paired with a town in a different country
-
-
One of two offspring born of a single gestation. Identical twins result from the division of a fertilized egg. Fraternal twins result from the fertilization of two separate eggs at the same time.
-
A crystal structure consisting of two intergrown crystals that are mirror images of each other. Mineral twins can form as result of defective crystal growth in response to stress from rock deformation or during magma cooling.
Other Word Forms
Derived Forms
Inflected Forms
Nouns
Etymology
Origin of twin
First recorded before 900; Middle English adjective twynne, twinne, Old English adjective twinn “twofold, double”; noun and adjective getwinn “double,” (plural getwinnas “twins”); akin to Old Frisian twīna, twīne “two together,” Old Norse tvinnr “double,” Gothic twaihnái “two each”
Explanation
When mammals have two babies at once, each of them is a twin. If you have a twin brother or sister, the two of you are always the same age. There are identical twins, who have the same DNA, and fraternal twins, who are more like two siblings who happen to be born at the same time. It's more common to describe humans as twins than other animals. The adjective twin can also describe a pair of things, like the twin chocolate cakes you serve at your birthday party or the "Twin Cities" in Minnesota, Minneapolis and St. Paul.
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.
See Examples For:
He and his twin sister were two years old when Madeleine, then aged three, went missing during a family holiday in Praia Da Luz, Portugal, in 2007.
From BBC ● Jul. 25, 2026
The twin artists and designers’ tiresomely juvenile works are the focus of this survey.
From The Wall Street Journal ● Jul. 24, 2026
Now, the Trump administration is facing a daunting multibillion-dollar cleanup after twin earthquakes last month tore open roads, downed power lines and flattened buildings.
From The Wall Street Journal ● Jul. 19, 2026
Being born a twin comes with certain expectations.
From Salon ● Jul. 18, 2026
He wouldn’t keep it a secret that I have a twin brother.
From "The Manifestor Prophecy" by Angie Thomas
Although these molecular twins can appear nearly identical, they may behave in dramatically different ways, particularly in living systems and medicines.
From Science Daily ● Jul. 28, 2026
The identical Roper twins created a slice of Wales team history as the gymnasts both won Commonwealth Games bronze in Glasgow within a couple of hours of each other.
From BBC ● Jul. 27, 2026
“Whimsical” is the word most frequently used to describe the work of artist-designer twins Nikolai and Simon Haas, who are the subject of a midcareer survey at the Museum of Arts and Design.
From The Wall Street Journal ● Jul. 24, 2026
One user told Palmer about how both their twins had died in their arms—one after 10 minutes, the other after 10 days.
From Slate ● Jul. 19, 2026
The prickling sensation on the back of his neck returned and he didn’t have the twins to explain it.
From "The Way to Rio Luna" by Zoraida Cordova
“The expanded tournament, twinned with its geographical span, means that it’s by far the most emissions-intensive World Cup that we’ve ever seen,” Daley said.
From Los Angeles Times ● May 18, 2026
Is it this twinned violence and fecundity that feeds our dread?
From The Wall Street Journal ● May 15, 2026
Months at first, then anniversaries, birthdays twinned in the mental calendar with dates of death.
From BBC ● Nov. 25, 2024
Congress held hearings in 2020 investigating the twinned tragedies in Ethiopia and Indonesia, crashes caused primarily by engineering mistakes at Boeing.
From Seattle Times ● Apr. 8, 2024
My nail-bitten fingers twinned with his, pale and webbed with purple veins.
From "Miss Peregrine's Home for Peculiar Children" by Ransom Riggs
Some are twinning a trip to the gym with coffee mornings or protein smoothie meet-ups - further boosting the social experience.
From BBC ● Mar. 21, 2026
But all those efforts at twinning are a bit futile.
From The Wall Street Journal ● Oct. 31, 2025
There’s a case to be made for the twinning of these events.
From Washington Post ● May 19, 2022
Jessica Beck, a curator at the Andy Warhol Museum in Pittsburgh, came up with the idea of twinning the artists as a way of reintroducing Marisol and showing the overlap of ideas and influence.
From New York Times ● Apr. 27, 2022
His spirit, depleted by his own depredations, pulsed too fast through his veins, twinning with a whirr and discordant jangle of...of disbelief crashing against evidence, producing a sensation of disfaith.
From "Strange the Dreamer" by Laini Taylor
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
