# twin

> English word · Noun · IPA /twɪn/ · frequency rank #4,054

## Definitions
1. Either of two people (or, less commonly, animals) who shared the same uterus at the same time; one who was born at the same birth as a sibling.
2. Either of two similar or closely related objects, entities etc.
3. A room in a hotel, guesthouse, etc. with two beds; a twin room.
4. A two-engine aircraft.
5. A twin crystal.
6. A twin size mattress; or a bed designed for such a mattress.
7. A friendly term of address, typically for men.

## Etymology
PIE word
 *dwóh₁
From Middle English twinne, twynne, from Old English ġetwin, ġetwinn (“twin, multiple”, noun) and twinn (“twin, two-fold, double, two by two”, adjective), from Proto-Germanic *twinjaz, *twinahz (“two each”), from Proto-Indo-European *dwino- (“twin”), from *dwóh₁ (“two”). Cognate with Scots twyn (“twin”), Dutch tweeling (“twin”), German Zwilling (“twin”), Danish tvilling (“twin”), Swedish tvilling (“twin”), Faroese tvinnur (“a double set”), Icelandic tvenna (“duo, pair”), Lithuanian dvynys (“twin”), Russian двойня (dvojnja, “twin”).

## Easily confused with
- **two** (https://plainspell.com/en/vs/twin-vs-two)
- **twp** (https://plainspell.com/en/vs/twin-vs-twp)
- **twos** (https://plainspell.com/en/vs/twin-vs-twos)
- **twit** (https://plainspell.com/en/vs/twin-vs-twit)
- **twist** (https://plainspell.com/en/vs/twin-vs-twist)
- **twins** (https://plainspell.com/en/vs/twin-vs-twins)
- **tying** (https://plainspell.com/en/vs/twin-vs-tying)
- **twine** (https://plainspell.com/en/vs/twin-vs-twine)
- **twink** (https://plainspell.com/en/vs/twin-vs-twink)
- **twirl** (https://plainspell.com/en/vs/twin-vs-twirl)
- **ti** (https://plainspell.com/en/vs/ti-vs-twin)
- **TN** (https://plainspell.com/en/vs/tn-vs-twin)
- **ten** (https://plainspell.com/en/vs/ten-vs-twin)
- **tip** (https://plainspell.com/en/vs/tip-vs-twin)
- **tie** (https://plainspell.com/en/vs/tie-vs-twin)
- **Tim** (https://plainspell.com/en/vs/tim-vs-twin)
- **ton** (https://plainspell.com/en/vs/ton-vs-twin)
- **tin** (https://plainspell.com/en/vs/tin-vs-twin)
- **tan** (https://plainspell.com/en/vs/tan-vs-twin)
- **tri** (https://plainspell.com/en/vs/tri-vs-twin)

## Common misspellings (6)
`tiwn`, `ttwin`, `twinn`, `twni`, `twwin`, `wtin`

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/twin