A straitjacket is a garment shaped like a jacket with overlong sleeves and is typically used to restrain a person who may otherwise cause harm to themselves or others. Once the arms are inserted into the straitjacket's sleeves, they are then crossed across the chest. The end of the sleeves are then tied to the back of the wearer, ensuring that the arms are kept close to the chest with as little movement as possible.

Although straitjacket is the most common spelling, strait-jacket is also frequently used, and in Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

 strait-waistcoat, which is generally deemed archaic

Archaism

In language, an archaism is the use of a form of speech or writing that is no longer current. This can either be done deliberately or as part of a specific jargon or formula...

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