Other forms: twins
A twin is one of two children born to the same mother on the same day. Identical twins, her twin brother, twin sisters.
Identical twins come from one egg that split and share their DNA; non-identical ones are simply two pregnancies at once. Twin studies are a foundation of research into what is inherited, because they separate nature from upbringing. Note twin as an adjective, meaning paired: twin beds, twin towns.
1nountwinOne of two children born at the same birth.
“She and her twin look so alike that even their teachers mix them up.”
2adjectivepairedPaired or matching.
“We asked for a room with twin beds, since we didn't want to share.”
Too few real examples of this word to estimate which sense is commonest.
twin is one of a pair.
Also accepted in games: twins
Old English getwinn means twofold or double, from a Germanic root meaning two. Twice and between come from the same two.
Proto-Indo-European
*dwóh₁
Proto-Germanic
*twinaz — double/two each, twin
Old English
ġetwin
Middle English
twinne
English, today
twin
Built from
From Middle English twinne, twynne, from Old English ġetwin, ġetwinn (“twin, multiple”) and twinn (“twin, two-fold, double, two by two”), 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”), {{cog|de|
Etymology from Wiktionary, CC BY-SA