n.
Pronunciation: ' twin
Function: noun
Etymology: Middle English, from twin twofold
Date: 14th century
1 a : either of two offspring produced at a birth b plural capitalized : 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
– twin · ship \ - ˌ ship \ noun