Added 9 October 2026

twin

/twɪn/ noun

In Latin: geminus, gemina, connascor Wiktionary

noun Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about twin at Wordnik → Where our words come from →

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.
twin girls, twin daughters, twin sisters, twin boys, twin sons, twin brothers, twin babies, twin children
Either of two similar or closely related objects, plans, institutions, people, etc.
Your idea is the twin of mine.
Either of two or more things, people, etc. that share a single feature.
He is my twin (wearing the same shirt, driving the same car, etc.).

To separate, divide.
To split, part; to go away, depart.
To join, unite; to form links between (now especially of two places in different countries); to pair with.
Reading, the English town, is twinned with Clonmel in Ireland.

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 *twinaz (“double/two each, twin”), Proto-Germanic *twinjaz, *twīhnaz (“two each”), from Proto-Indo-European *dwino- (“twin”), from *dwóh₁ (“two”). Cognate with Scots twyn (“twin”), Dutch tweeling (“twin”), German Zwilling (“twin”), Danish, Norwegian Bokmål, Norwegian Nynorsk, and Swedish tvilling (“twin”), Faroese tvinnur (“a double set”), Icelandic tvenna (“duo, pair”), Lithuanian dvynys (“twin”), Russian двойня (dvojnja, “twin”).