twin

1 of 3

noun

ˈtwin How to pronounce twin (audio)
Synonyms of twinnext
1
a
: 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
twinship
ˈtwin-ˌship How to pronounce twin (audio)
noun

twin

2 of 3

adjective

1
: born with one other or as a pair at one birth
my twin brother
twin girls
2
a
: made up of two similar, related, or connected members or parts : double
a twin-engine airplane
b
: paired in a close or necessary relationship : matching
the company's twin goals of greater productivity and profits
c
: having or consisting of two identical units
d
: being one of a pair

twin

3 of 3

verb

twinned; twinning

transitive verb

1
: to bring together in close association : couple
2
: duplicate, match

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

Synonyms of twin

Relevance

Noun

Adjective

See All Synonyms & Antonyms in Thesaurus

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
In the throwback snap, the twins could be seen doing a cannonball into the pool. — Kayla Grant, PEOPLE, 6 Aug. 2026 As Twins designated hitter Josh Bell, who walked to begin the frame, barreled toward second base, Massey attempted to tag him in the basepaths. — Kansas City Star, 6 Aug. 2026
Adjective
Of course, Kies has also learned plenty along the way from his twin brother. — Steve Millar, Chicago Tribune, 7 Aug. 2026 Her son was getting married soon, and her twin daughters were twenty-five. — The New Yorker, New Yorker, 7 Aug. 2026
Verb
The very next day, they were spotted yet again, in #twinning athleisure looks of gym shorts, sleeveless T-shirts, baseball caps, workout kicks, and, again, cross-body bags. — Max Berlinger, Vogue, 5 Aug. 2026 The Geres started twinning when Homer was just over 1 year old. — Kelly Allen, PEOPLE, 1 Aug. 2026 See All Example Sentences for twin

Word History

Etymology

Noun

Middle English, from twin twofold

Adjective

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

First Known Use

Noun

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

Adjective

1593, in the meaning defined at sense 1

Verb

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

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

Phrases Containing twin

Rhymes for twin

See All Rhymes for twin

Browse Nearby Words

TWIMC
twin
twin-axis
See all Nearby Words

Cite this Entry

“Twin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/twin. Accessed 8 Aug. 2026.

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Kids Definition

twin

1 of 3 adjective
ˈtwin How to pronounce twin (audio)
1
: born with one other or as a pair at one birth
my twin brother
twin girls
2
a
: made up of two similar, related, or connected members or parts
b
: being one of a pair
a twin city

twin

2 of 3 verb
twinned; twinning
: to produce or give birth to twins

twin

3 of 3 noun
: either of two offspring produced at a birth compare fraternal twin, identical twin

Medical Definition

twin

1 of 2 adjective
ˈtwin How to pronounce twin (audio)
: born with one other or as a pair at one birth
a twin brother
twin girls

twin

2 of 2 noun
1
: either of two offspring produced at a birth
2
twins plural : a group of two offspring born at one birth
twinship
-ˌship How to pronounce twin (audio)
noun

More from Merriam-Webster on twin

Nglish: Translation of twin for Spanish Speakers

Britannica.com: Encyclopedia article about twin

Last Updated: - Updated example sentences
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