1. Two; a pair.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• twinz,
• twhen,
• twail,
• teaing,
• twing,
• tiwan,
• waitn,
• tiwain,
• tworn,
• taine,
• ttrain,
• twinn,
• towait,
• awaing,
• teamin,
• teain,
• hawain,
• twian,
• twaht,
• togain

• twine,
• twin,
• Twanna,
• Twana.

The adjective form of the word "twain" is "twin".

The plural of the "twain" can be the "twains".

The singular of the "twain" can be the "twain".