twin

1 of 3

noun

ˈtwin 

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 

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

b

: paired in a close or necessary relationship : matching

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

Noun

• companion
• fellow
• half
• match
• mate

Adjective

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

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

Noun

Austin was stabbed in the heart and died in the arms of his twin brother, the twins’ father said. —Shambhavi Rimal, Fort Worth Star-Telegram, 4 Apr. 2025

Lopez shares her twins Emme and Max, 17, with ex Marc Anthony. —Hannah Sacks, People.com, 4 Apr. 2025

Adjective

Two years later, Cooper and his twin brother, Ace, arrived. —Samantha Stutsman, People.com, 6 Apr. 2025

Cannon's twin sister, Monroe, then approaches the camera holding a white dog. —Wesley Stenzel, EW.com, 5 Apr. 2025

Verb

Essentials Winter Green Mattress is perfect for all sleep positions and on sale in sizes twin through split California king. —Miles Walls, Better Homes & Gardens, 5 Apr. 2025

Even more troubling, the dramatic increase in home prices since the covid-19 pandemic twinned with supply constraints have put the housing market on ice. — Made By History, TIME, 25 Mar. 2025

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

Phrases Containing twin

• conjoined twin
• fraternal twin
• identical twin
• Siamese twin
• twin bed
• twin-bedded
• twin bill
• twin double
• twin primes
• twin-size
• twin town
• twin-turbo

Rhymes for twin

• been
• bin
• chin
• din
• djinn
• fin
• finn
• gin
• grin
• in
• kin
• linn

Kids Definition

twin

1 of 3 adjective

ˈtwin 

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 

: 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 

noun